This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use PRECISE LANGUAGE and DOMAIN-SPECIFIC VOCABULARY—this means using technical terms appropriate to the subject area instead of vague, everyday words. Emma writes about Earth's movement in Earth science. Version 1 uses everyday language ("spins" and "goes around") while Version 2 uses precise, domain-specific vocabulary ("rotates," "axis," "revolves," and "orbit"). The technical terms in Version 2 are the standard scientific vocabulary for describing Earth's movements. Choice B is correct because Version 2 uses precise, domain-specific language with technical terms like "rotates" (instead of "spins"), "axis," "revolves" (instead of "goes around"), and "orbit" while Version 1 uses vague, everyday words which are less precise. These technical terms are standard in Earth science and make the explanation more accurate and professional. Choice A is incorrect because "spins" and "goes around" are everyday words, not technical terms—they're the vague language that should be replaced with domain vocabulary like "rotates" and "revolves." To help students use precise language and domain-specific vocabulary: Compare vague vs precise examples side-by-side as shown here; teach science-specific terms: "Earth doesn't just 'spin'—it rotates on its axis. Earth doesn't just 'go around'—it revolves in an orbit."; create charts showing everyday language → domain vocabulary conversions. Watch for: students who think everyday words like "spins" are technical enough; students who don't know the precise terms for common phenomena; use comparisons like this to show the difference between general and domain-specific language; emphasize that scientific writing requires scientific vocabulary.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use PRECISE LANGUAGE and DOMAIN-SPECIFIC VOCABULARY—this means using technical terms appropriate to the subject area instead of vague, everyday words. DOMAIN-SPECIFIC VOCABULARY = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Sofia writes about landforms in geography/social studies. The explanation uses precise language and domain-specific vocabulary such as: "peninsula" which is an appropriate technical term for geography. The word "peninsula" is the key domain-specific vocabulary that precisely names this type of landform. Choice A is correct because "peninsula" is domain-specific vocabulary—a technical term that correctly and precisely describes a landform in geography, instead of vague words. This geographic term is precise and specific to the subject area, making the explanation clear and accurate. Choice B is incorrect because "almost" is not domain-specific vocabulary—it's a general adverb that could be used in any subject, not a technical geography term. Students sometimes confuse general descriptive words with domain-specific vocabulary. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with social studies/geography terms—display with definitions; teach technical terms directly: "When explaining landforms, use these precise terms: peninsula (land almost surrounded by water), island (land completely surrounded by water), isthmus (narrow strip connecting two larger land areas)"; model identifying domain vocabulary: "I see Sofia used 'peninsula'—that's domain vocabulary! It's the technical geography term for this landform."; practice recognizing domain terms: give sentences, students identify which words are subject-specific. Emphasize precision purpose: "Domain vocabulary makes your explanation clearer. 'Peninsula' tells exactly what type of landform—not just 'land near water.'"; teach subject-appropriate terms: geography topics need geography vocabulary; highlight domain words when reading informational text; give feedback: "Good use of domain vocabulary: 'peninsula' is the precise geography term!" Watch for: students who can't distinguish between domain-specific terms and general descriptive words; students who think any word in the sentence might be domain vocabulary; students who don't understand that each subject has specific technical terms; teach explicitly: domain vocabulary consists of technical terms specific to each subject area.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words. Domain-specific vocabulary = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Precise vs vague: Precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); Vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise). Precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); Vague = 'Water goes up into the air when it gets hot' (general words). Why it matters: Domain vocabulary makes explanations clearer and more accurate; shows understanding of subject; provides specific, exact meaning; is standard in each field (scientists say 'evaporation' not 'water going up'). Using precise, subject-specific language is important in informational writing to communicate accurately. Marcus writes about voting in social studies (civics). The explanation uses precise language and domain-specific vocabulary such as 'democracy,' 'citizens,' 'vote,' 'election,' 'representatives' which are appropriate technical terms for social studies. Choice A is correct because Marcus uses precise language and domain-specific vocabulary—technical terms like 'democracy,' 'citizens,' 'vote,' 'election,' 'representatives' are appropriate for social studies and make the explanation clear and accurate. Choice B is incorrect because it confuses everyday phrases ('choose,' 'people') with technical terms; students sometimes think general, descriptive words are precise enough. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'); use frayer model for vocabulary: term in center, definition, characteristics, examples, non-examples; require vocabulary use in writing: 'Your explanation must include these domain terms: habitat, adaptation, predator, prey.'. Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer. “Evaporation” tells exactly what happens—“water going up” is vague.'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations.”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed. Predator is the hunter, prey is hunted.'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'. Watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'). Common pitfall: students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words; domain-specific vocabulary includes technical terms from the subject like science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation), social studies (hemisphere, representative, peninsula, primary source, citizen, democracy), or math (perimeter, numerator, variable, parallel); precise vs vague: precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise); precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); vague = 'Water goes up into the air when it gets hot' (general words); why it matters: domain vocabulary makes explanations clearer and more accurate, shows understanding of subject, provides specific, exact meaning, and is standard in each field (scientists say 'evaporation' not 'water going up'); using precise, subject-specific language is important in informational writing to communicate accurately. Yuki writes about using sources in history in social studies; the explanation uses precise language and domain-specific vocabulary such as 'primary source,' 'secondary source,' and 'artifact' which are appropriate technical terms for social studies. Choice C is correct because Yuki uses domain vocabulary like 'primary source,' 'secondary source,' and 'artifact' which correctly and precisely describe concepts in social studies, instead of vague words. Choice A is incorrect because it suggests vague replacements instead of more precise domain vocabulary; students sometimes suggest vague replacements instead of more precise domain vocabulary. To help students use precise language and domain-specific vocabulary: build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'). Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer; “evaporation” tells exactly what happens—“water going up” is vague'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed; predator is the hunter, prey is hunted'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'; watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'); students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words. Domain-specific vocabulary = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Precise vs vague: Precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); Vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise). Precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); Vague = 'Water goes up into the air when it gets hot' (general words). Why it matters: Domain vocabulary makes explanations clearer and more accurate; shows understanding of subject; provides specific, exact meaning; is standard in each field (scientists say 'evaporation' not 'water going up'). Using precise, subject-specific language is important in informational writing to communicate accurately. Emma writes about the water cycle in science. The explanation uses vague, everyday language such as 'goes up,' 'makes clouds,' 'comes down' instead of domain vocabulary; it mixes some precise terms like 'water cycle' with vague words like 'goes up' and 'comes down.' Choice A is correct because Emma could make her language more precise by replacing 'goes up' with 'evaporation,' 'makes clouds' with 'condensation,' and 'comes down' with 'precipitation' because these technical terms are more accurate and clear for science writing. Choice B is incorrect because it accepts vague words like 'goes up' or 'comes down' as precise vocabulary when domain-specific terms would be more accurate; students sometimes use everyday language ('water going up') instead of technical terms ('evaporation'). To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'); use frayer model for vocabulary: term in center, definition, characteristics, examples, non-examples; require vocabulary use in writing: 'Your explanation must include these domain terms: habitat, adaptation, predator, prey.'. Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer. “Evaporation” tells exactly what happens—“water going up” is vague.'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations.”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed. Predator is the hunter, prey is hunted.'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'. Watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'). Common pitfall: students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use PRECISE LANGUAGE and DOMAIN-SPECIFIC VOCABULARY—this means using technical terms appropriate to the subject area instead of vague, everyday words. DOMAIN-SPECIFIC VOCABULARY = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Carlos writes about space in earth science. The explanation uses vague, everyday language such as "goes around" and "spins" instead of domain vocabulary. He should replace "goes around" with "orbit" and "spins" with "rotation" to use precise, technical terms. Choice A is correct because Carlos should replace vague words—"goes around" should become "orbit" (the technical term for Earth's path around the Sun) and "spins" should become "rotation" (the technical term for Earth turning on its axis), making the explanation more precise with appropriate earth science vocabulary. These domain-specific terms accurately describe Earth's movements in space. Choice B is incorrect because it suggests replacing the precise term "Sun" with the vague phrase "big light"—this would make the writing less precise, not more precise, as "Sun" is already the correct astronomical term. Students sometimes don't understand that we should replace vague words with technical terms, not the reverse. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with earth science/astronomy terms—display with definitions; teach technical terms directly before writing: "When explaining Earth's movements, use these precise terms: orbit (path around the Sun), rotation (spinning on axis), revolution (complete orbit), axis—not vague words like 'goes around' or 'spins'"; model replacing vague with precise: "I wrote 'Earth goes around the Sun.' Too vague! Replace: 'Earth orbits the Sun.' Now I used domain vocabulary: orbits."; practice precision substitutions: give sentences with everyday language, students replace with science terms. Emphasize precision purpose: "Domain vocabulary makes your explanation clearer. 'Orbit' tells exactly how Earth moves around the Sun—'goes around' is vague."; compare vague vs precise examples side-by-side; teach astronomy-appropriate terms; provide vocabulary banks during writing; give feedback: "Replace 'goes around' with domain vocabulary: 'orbits.'" Watch for: students who use everyday descriptions ("goes around," "spins") instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who want to replace precise terms with vague ones; teach explicitly: scientific writing uses technical vocabulary to be accurate and clear.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words. Domain-specific vocabulary = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Precise vs vague: Precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); Vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise). Precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); Vague = 'Water goes up into the air when it gets hot' (general words). Why it matters: Domain vocabulary makes explanations clearer and more accurate; shows understanding of subject; provides specific, exact meaning; is standard in each field (scientists say 'evaporation' not 'water going up'). Using precise, subject-specific language is important in informational writing to communicate accurately. Chen writes about rocks in science (earth science). The explanation uses precise language and domain-specific vocabulary such as 'metamorphic rock' which is an appropriate technical term for science, but uses it incorrectly with 'melts and cools.' Choice B is correct because Chen does NOT use precise language—the explanation uses domain vocabulary like 'metamorphic rock' which is present but incorrectly describes the concept in science, as metamorphic forms from heat and pressure, not melting and cooling. Choice A is incorrect because it doesn't notice technical term is used incorrectly; students sometimes use technical terms incorrectly. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'); use frayer model for vocabulary: term in center, definition, characteristics, examples, non-examples; require vocabulary use in writing: 'Your explanation must include these domain terms: habitat, adaptation, predator, prey.'. Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer. “Evaporation” tells exactly what happens—“water going up” is vague.'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations.”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed. Predator is the hunter, prey is hunted.'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'. Watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'). Common pitfall: students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words; domain-specific vocabulary includes technical terms from the subject like science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation), social studies (hemisphere, representative, peninsula, primary source, citizen, democracy), or math (perimeter, numerator, variable, parallel); precise vs vague: precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise); precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); vague = 'Water goes up into the air when it gets hot' (general words); why it matters: domain vocabulary makes explanations clearer and more accurate, shows understanding of subject, provides specific, exact meaning, and is standard in each field (scientists say 'evaporation' not 'water going up'); using precise, subject-specific language is important in informational writing to communicate accurately. Jamal writes about Arctic foxes in life science; the explanation uses vague, everyday language such as 'stuff,' 'cold places,' and 'bigger animals' instead of domain vocabulary; if precise: he should use specific domain vocabulary like 'adaptation,' 'camouflage,' 'habitat,' and 'predator' correctly. Choice B is correct because Jamal does not use precise language—the explanation uses vague, everyday words like 'stuff' and 'cold places' instead of domain-specific vocabulary like 'adaptation,' 'camouflage,' and 'habitat' which would be more precise for this science topic. Choice A is incorrect because it claims the explanation uses precise language when technical terms are missing; students sometimes use vague words like 'stuff,' 'things,' 'place' instead of technical terms. To help students use precise language and domain-specific vocabulary: build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'). Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer; “evaporation” tells exactly what happens—“water going up” is vague'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed; predator is the hunter, prey is hunted'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'; watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'); students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words. Domain-specific vocabulary = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Precise vs vague: Precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); Vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise). Precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); Vague = 'Water goes up into the air when it gets hot' (general words). Why it matters: Domain vocabulary makes explanations clearer and more accurate; shows understanding of subject; provides specific, exact meaning; is standard in each field (scientists say 'evaporation' not 'water going up'). Using precise, subject-specific language is important in informational writing to communicate accurately. Yuki writes about sources in social studies (history). The explanation uses precise language and domain-specific vocabulary such as 'primary source' which is an appropriate technical term for social studies but mixes it with vague words like 'old thing' and 'back then.' Choice A is correct because Yuki should replace vague words like 'old thing' with domain vocabulary 'artifact or document made during the time' to make the explanation more precise. Choice B is incorrect because it suggests vague replacements instead of more precise domain vocabulary; students sometimes use everyday language instead of domain vocabulary. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'); use frayer model for vocabulary: term in center, definition, characteristics, examples, non-examples; require vocabulary use in writing: 'Your explanation must include these domain terms: habitat, adaptation, predator, prey.'. Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer. “Evaporation” tells exactly what happens—“water going up” is vague.'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations.”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed. Predator is the hunter, prey is hunted.'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'. Watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'). Common pitfall: students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.

This question tests 4th grade informational/explanatory writing skills: using precise language and domain-specific vocabulary to inform about or explain the topic (CCSS.W.4.2.d). Informational and explanatory writing should use precise language and domain-specific vocabulary—this means using technical terms appropriate to the subject area instead of vague, everyday words. Domain-specific vocabulary = technical terms from the subject: Science (habitat, adaptation, metamorphosis, predator, prey, evaporation, condensation, friction, orbit, precipitation); Social Studies (hemisphere, representative, peninsula, primary source, citizen, democracy); Math (perimeter, numerator, variable, parallel). Precise vs vague: Precise = 'The carnivore hunts prey in its habitat' (technical terms: carnivore, prey, habitat make meaning clear); Vague = 'The animal that eats meat finds food where it lives' (everyday words, less precise). Precise = 'Evaporation occurs when liquid water becomes water vapor' (technical: evaporation, liquid, water vapor); Vague = 'Water goes up into the air when it gets hot' (general words). Why it matters: Domain vocabulary makes explanations clearer and more accurate; shows understanding of subject; provides specific, exact meaning; is standard in each field (scientists say 'evaporation' not 'water going up'). Using precise, subject-specific language is important in informational writing to communicate accurately. Jamal writes about fractions in math. The explanation uses vague, everyday language such as 'top number' and 'bottom number' instead of domain vocabulary. Choice A is correct because Jamal should add domain-specific vocabulary like 'numerator' and 'denominator' which correctly and precisely describe the concepts in math, instead of vague words. Choice B is incorrect because it confuses everyday phrases with technical terms and identifies words that aren't actually technical terms for this subject; students sometimes don't know or avoid subject-specific vocabulary. To help students use precise language and domain-specific vocabulary: Build domain vocabulary explicitly for each subject unit; create word walls with science terms, social studies terms, math terms—display with definitions; teach technical terms directly before writing: 'When explaining water cycle, use these precise terms: evaporation (liquid→vapor), condensation (vapor→liquid), precipitation (water falling)—not vague words like “water goes up” or “water comes down”'; model replacing vague with precise: 'I wrote “The animal lives in a place.” Too vague! Replace: “The arctic fox inhabits the tundra habitat.” Now I used domain vocabulary: inhabits, tundra, habitat.'; practice precision substitutions: give sentences with vague language, students replace with domain terms ('The rock formed from hot stuff' → 'The igneous rock formed from cooled lava'); use frayer model for vocabulary: term in center, definition, characteristics, examples, non-examples; require vocabulary use in writing: 'Your explanation must include these domain terms: habitat, adaptation, predator, prey.'. Emphasize precision purpose: 'Domain vocabulary makes your explanation clearer. “Evaporation” tells exactly what happens—“water going up” is vague.'; compare vague vs precise examples side-by-side; teach subject-appropriate terms: science topics need science vocabulary, social studies topics need social studies terms; provide vocabulary banks during writing; give feedback: 'Replace “stuff” with domain vocabulary: “adaptations.”' or 'Use precise term “hemisphere” instead of “half of Earth”'; practice reading informational text, identify domain vocabulary authors use; teach correct usage: 'Predator hunts prey, not reversed. Predator is the hunter, prey is hunted.'; encourage defining terms: 'Metamorphosis—the transformation from larva to adult—takes weeks'. Watch for: students who use vague words like 'stuff,' 'things,' 'place' instead of technical terms; students who avoid domain vocabulary because unfamiliar; students who use everyday language ('water going up') instead of technical terms ('evaporation'). Common pitfall: students who mix precise and vague in same writing; students who use technical terms incorrectly; students who don't understand that domain vocabulary varies by subject; students who think any descriptive word is precise; students who don't define technical terms when introducing them; teach explicitly: informational writing uses subject-specific vocabulary to be clear and accurate.