Subject-Verb Agreement
Subject-verb agreement (also called concord) is the grammatical requirement that the verb matches its subject in number and person. In English, this is morphologically simple — only the third person singular present tense carries the -s inflection (she writes vs they write) — yet it remains a persistent source of errors for L2 learners.
Basic Rule
| Subject | Verb | Example |
|---|---|---|
| Singular (3rd person) | -s form | The student writes. |
| Plural / 1st / 2nd person | base form | The students write. / I write. |
The verb be is the only English verb with fuller agreement: am/is/are (present), was/were (past).
Problem Areas
Intervening Phrases
The subject and verb may be separated by prepositional phrases, relative clauses, or parenthetical expressions:
- The quality of the essays is impressive. (not *are — head noun is quality)
- The students in the class are motivated.
Collective Nouns
British and American English differ:
- BrE: The team are playing well. (members acting individually)
- AmE: The team is playing well. (treated as singular unit)
Quantifiers and Determiners
- Each/every/either/neither + singular verb: Every student has a book.
- All/some/most/any — depends on the noun: Some water is* / Some books are
- A number of + plural verb; The number of + singular verb
Existential There
The verb agrees with the notional subject that follows — see Existential There:
- There is a cat on the mat.
- There are three cats on the mat.
In informal speech, there's often precedes plural subjects (There's three cats), which is standard in spoken English but marked in formal writing.
Other Tricky Cases
- Compound subjects: Tom and Jerry are / Bread and butter is (single concept)
- Relative clauses: She is one of those students who are always prepared (not is — antecedent is students)
- Indefinite pronouns: Everyone has / None is/are (both accepted)
- Titles and names: The United States is / "The Grapes of Wrath" is
Why Errors Persist
Despite the apparent simplicity of English agreement, errors are remarkably persistent because:
- Processing load — agreement errors increase when the subject-verb distance is greater or when the intervening noun has different number from the head noun (attraction errors)
- L1 transfer — languages with richer agreement systems (Spanish, Arabic) may transfer different patterns; languages with no agreement (Vietnamese, Chinese) may omit the -s entirely
- Low communicative cost — agreement errors rarely impede communication, so there is little pressure to eliminate them
- Spoken English — contracted and reduced forms (there's, it's) obscure agreement distinctions
Teaching Implications
- Focus on high-frequency problem areas (there is/are, collective nouns, intervening phrases) rather than exhaustive rule coverage
- Editing tasks targeting agreement are effective — learners can often correct errors they produce
- Oral practice with real-time self-monitoring helps build Automaticity