Subject-Verb Agreement: Ten Rules

The verb must agree with its subject in number: singular subject → singular verb; plural subject → plural verb.

1. Find the real subject

Ignore phrases between the subject and the verb.

2. "And" makes a plural

But if both nouns refer to one person or idea, use a singular verb: The poet and philosopher is dead. Bread and butter is my breakfast.

3. Each, every, either, neither, everyone, somebody → singular

4. Either…or / neither…nor / not only…but also → the nearer subject decides

5. With, along with, as well as, together with, besides → the first subject decides

6. Collective nouns

Singular when the group acts as one unit; plural when members act separately.

7. Uncountable nouns and words ending in -s that are singular

8. Plural-only nouns take a plural verb

9. Amounts as one unit → singular

10. "A number of" vs "the number of"

Also: Many a man has tried (singular), and in there is/are sentences the verb agrees with the noun that follows: There are two mistakes.