Subject-Verb Agreement
Subjects and verbs must “agree” in number (singular or plural) and person. The concept of agreement is particularly relevant to:
1) the present simple tense: subjects in 3 rd person singular (he, she, it) take verbs with the ending -s
2) the verb to be: it can take forms am/is/are and was/were
3) the verb to have: it can take forms have/has
Note: If a sentence contains a modal verb (e.g. should, can, could, must, may), this modal must be followed by the base form of the verb regardless of the subject’s number and person. For example: The witness must report to the police (not must reports).
Below are the rules for subject-verb agreement.
- Make sure the verb agrees with its subject, not with a word that comes between the subject and the verb (whether in preposition phrases or adjective clauses).For example: The samples on the tray in the lab need testing. (prepositional phrases)
The governor, as well as his press secretary, was applauded. (an adjective clause) Note: A subject can never be a part of a prepositional phrase (e.g. in the lab is a prepositional phrase because it starts with the preposition in, so the noun lab cannot be a subject of a sentence).
- Make the verb agree with its subject even when the subject comes after the verb.
For example: Matt and Lisa often write in the morning.
Sonja’s ability and desire to help are inspiring.
However, when the parts of the subject form a single unit or when they refer to the same person or thing, treat the subject as singular. In addition, when a compound subject is preceded by each or every, treat the subject as singular.
Adapted from: A Writer’s Reference (7th ed.) by Diana Hacker.
Grammar & Style
- Converting Fragments to Full Sentences
- Active and Passive Voice
- Choosing Between Infinitive and Gerund: “To do” or “doing”?
- Choosing the Correct Word Form
- Combining Clauses to Avoid Comma Splices, Run-ons, and Fragments
- Commas, Semicolons, and Colons
- Count vs. Noncount Nouns
- Definite and Indefinite Articles
- Improving Cohesion: The "Known/New Contract"
- Modal Verbs
- Parallel Structure
- Prepositions
- Pronouns
- Proper Nouns
- Reducing Informality in Academic Writing
- Run-on Sentences
- Same Form, but Different Functions: Various Meanings of Verb+ing and Verb+ed
- Subject-Verb Agreement
- The Three Common Tenses Used in Academic Writing
- Using Reduced Relative Clauses to Write Concisely
- Verb Tenses
- Word Order in Statements with Embedded Questions