Historical Context & Motivation
The principle of subject–verb agreement is among the oldest and most enduring rules of English grammar, rooted in the inflectional morphology inherited from Old English and, before that, Proto-Germanic. In highly inflected languages, verbs shift form to match the person, number, and sometimes gender of their subjects—a phenomenon called concord. Although Modern English has shed most of its inflectional endings, the requirement that a singular subject take a singular verb and a plural subject take a plural verb persists as a cornerstone of standard written English. For graduate-level examinees preparing for the HESI A2, this rule is not merely academic; it surfaces repeatedly in clinical documentation, research reporting, and professional communication, where a single agreement error can introduce ambiguity into patient care directives or data analysis.
The central question this lesson addresses is deceptively straightforward: how does a writer consistently identify the true subject of a sentence—stripping away intervening phrases, inverted syntax, and compound structures—and then select the verb form that agrees with it in number? The challenge lies not in the rule itself but in the numerous syntactic constructions that obscure the relationship between subject and verb, particularly in the complex, information-dense sentences characteristic of scientific and clinical writing.
Core Principles of Subject–Verb Agreement
At its most fundamental level, subject–verb agreement requires that a singular subject pairs with a singular verb and a plural subject pairs with a plural verb. In English, this distinction is most visible in the present tense, where the third-person singular verb typically takes an '-s' or '-es' suffix ("she runs"), while the plural form does not ("they run"). Although the rule appears simple, its application demands an ability to parse sentence architecture and identify the grammatical subject amidst modifying phrases, appositives, and clausal embeddings.
Identify the True Subject
Compound Subjects & Conjunctions
Indefinite Pronouns
Inverted Sentence Order
Collective Nouns
Visual Explanation: Parsing the Subject–Verb Relationship
The visual above encapsulates the most common source of subject–verb agreement errors on the HESI A2: the proximity trap. When a prepositional phrase, appositive, or relative clause intervenes between the subject and the verb, writers tend to match the verb to the nearest noun rather than to the grammatical subject. The solution is systematic: mentally strip away all modifying phrases, locate the simple subject, determine its number, and then select the verb form that agrees. This parsing strategy—illustrated by the bracketed prepositional phrase in the diagram—becomes second nature with deliberate practice and is especially critical when reading and correcting sentences on a timed exam.
How Subject–Verb Agreement Works: Rules & Patterns
Rule 1: Prepositional Phrases Do Not Affect Agreement
A prepositional phrase beginning with words such as "of," "in," "with," "along with," "together with," "as well as," or "in addition to" never changes the number of the subject. The phrase "along with her colleagues" in the sentence "The researcher, along with her colleagues, presents the findings" is parenthetical; the subject is still "researcher" (singular), so the verb takes the singular form. This rule is particularly relevant in clinical and research contexts where authors frequently embed qualifying phrases between subjects and verbs.
Rule 2: Compound Subjects
When two or more subjects are joined by "and," the compound subject is plural: "Medication adherence and patient education are essential." The exception arises when two nouns refer to a single entity or concept: "Macaroni and cheese is a comfort food." When subjects are joined by "or," "nor," "either...or," or "neither...nor," the verb agrees with the subject nearest to it: "Neither the attending physician nor the residents were available."
Rule 3: Indefinite Pronouns
| Always Singular | Always Plural | Depends on Context |
|---|---|---|
| each, every, everyone, everybody, everything | both, few, many, several | all, any, more, most, none, some |
| anyone, anybody, anything | others | Agree with the noun in the "of" phrase: "Some of the data is…" vs. "Some of the patients are…" |
| either, neither, one, no one, nobody, nothing |
Rule 4: Inverted Sentences & Expletive Constructions
In sentences beginning with "there" or "here," the subject follows the verb. These words are expletives (grammatical placeholders) and never function as subjects. To determine agreement, mentally rearrange the sentence: "There are several contraindications" becomes "Several contraindications are there." The plural subject "contraindications" demands the plural verb "are." Similarly, questions often invert subject and verb: "Does the patient exhibit symptoms?" correctly uses the singular auxiliary "does" with the singular subject "patient."
Rule 5: Collective Nouns & Special Cases
Collective nouns—"committee," "team," "staff," "group," "family"—are singular when the group acts as one unit and plural when individual members act separately. In American English, the singular interpretation predominates: "The committee has decided on a new protocol." Nouns that are plural in form but singular in meaning—such as "news," "mathematics," "measles," and "physics"—take singular verbs. Conversely, nouns like "scissors," "trousers," and "proceeds" are always plural: "The proceeds were donated to the clinic."
Tricky Cases & Common HESI A2 Patterns
Relative Clauses
When a relative pronoun ("who," "which," "that") serves as the subject of a clause, the verb agrees with the pronoun's antecedent. Consider: "She is one of those nurses who go above and beyond." Here, "who" refers to "nurses" (plural), so the verb is plural. However, "She is the only one of the nurses who goes above and beyond" uses a singular verb because "the only one" narrows the antecedent to a single individual. This distinction is a frequent source of error on standardized exams and demands careful attention to meaning.
Titles, Measurements, and Amounts
Titles of works, names of organizations, and words referred to as words are always singular: "'Fundamentals of Nursing' is required reading." Amounts and measurements treated as a single unit are also singular: "Five milligrams is the standard dosage" and "Three hours is sufficient for the infusion." This convention appears regularly in clinical documentation and is tested on the HESI A2.
Worked Example: Correcting Agreement Errors
The following worked example mirrors the format and complexity of HESI A2 grammar items. We will walk through a multi-step correction process that applies several of the rules covered in previous sections.
Common Pitfalls vs. Effective Strategies
| Common Pitfall | Example of Error | Effective Strategy |
|---|---|---|
| Proximity attraction | "The efficacy of the treatments were proven." (verb agrees with "treatments" instead of "efficacy") | Cross out all prepositional phrases; match verb to the remaining noun. |
| Indefinite pronoun confusion | "Everyone in the clinical rotations have completed the module." ("everyone" is singular) | Memorize the singular/plural/variable indefinite pronoun categories. |
| Inverted-order oversight | "There is several risk factors to consider." ("risk factors" is plural) | Rearrange "there is/are" sentences to place the subject first. |
| Collective noun ambiguity | "The nursing staff are meeting at 3 PM." (in American English, "staff" as a unit is singular) | Determine whether the group acts as one unit or as individuals; prefer singular in formal American English. |
| Or/nor agreement error | "Neither the surgeon nor the nurses was prepared." (verb should agree with nearer subject "nurses") | With or/nor, always match the verb to the subject closest to it. |
Beyond Basic Agreement: Advanced Nuances
While the HESI A2 primarily tests standard agreement rules, understanding the broader landscape of agreement phenomena strengthens your ability to analyze complex sentences and prepares you for the kind of academic and clinical writing required in graduate programs. The table below contrasts the standard rules tested on the HESI A2 with more advanced considerations encountered in research writing and graduate-level prose.
| Standard HESI A2 Rule | Advanced / Graduate-Level Nuance |
|---|---|
| Collective nouns are singular when acting as a unit. | In British English and some medical journals, collective nouns routinely take plural verbs ("The WHO have recommended..."). Know your target style guide. |
| "None" can be singular or plural depending on the referent. | Historically, "none" was treated as strictly singular ("not one"). Modern usage and the APA Publication Manual accept plural when referring to a countable set: "None of the participants were excluded." |
| "Data" is treated as either singular or plural. | In scientific writing, "data" is increasingly accepted as a mass noun (singular: "The data suggests..."), but many style guides in health sciences still require the traditional plural: "The data indicate..." Check institutional requirements. |
| The subject of a gerund phrase is the gerund itself (singular). | Complex nominal clauses ("What the researchers discovered was/were multiple anomalies") create notional agreement tensions. Formal grammar uses singular; notional grammar may use plural when the predicate nominative is plural. |
| Amounts and measurements are singular when expressing a total. | When the individual components are emphasized, plural is appropriate: "Two hundred milligrams were administered in separate doses" (emphasizing discrete administrations). |
As you advance into graduate coursework, you will encounter style-guide-specific conventions that may appear to contradict the prescriptive rules tested on standardized exams. The key is to internalize the standard rules first—these are what the HESI A2 tests—and then layer on discipline-specific conventions as required by your program's style manual, whether APA, AMA, or a particular journal's guidelines. Mastering the foundational rules equips you to recognize when a deviation is intentional and contextually appropriate versus when it constitutes a genuine error.
Practice Problems
Lesson Summary
Subject–verb agreement requires that every verb match its grammatical subject in number, regardless of intervening prepositional phrases, appositives, or relative clauses that may separate them. Compound subjects joined by "and" are plural, while those joined by "or" or "nor" agree with the nearer subject. Indefinite pronouns fall into three categories—always singular ("each," "everyone"), always plural ("few," "many"), and variable ("all," "some," "none")—and must be memorized. In inverted sentences beginning with "there" or "here," the true subject follows the verb and must be identified before agreement can be determined.
The systematic strategy for HESI A2 success is to strip away modifying phrases, locate the simple subject, determine its number, and match the verb accordingly. Collective nouns are singular when the group acts as a unit, and amounts and measurements functioning as a single quantity take singular verbs. Mastering these rules not only prepares you for the exam but also ensures precision in the clinical and academic writing that defines graduate-level healthcare communication.