Which sentence uses a verb that agrees with its subject?

Question

A.
The snails in the garden moves slowly.


B.
A bag of groceries were found outside the store.


C.
The stripes on the American flag are white and red.


D.
Authors of books receives royalties for their work.

Answer 1

Subject-verb agreement means that a singular noun has to have a singular verb, and likewise a plural noun has to have a plural verb to match it. So for example:

They (plural noun) are (plural verb) funny.

He (singular noun) is (singular verb) funny.

A helpful tip for English subject-verb agreement: singular verbs tend to have -s at the end, whereas plural verbs don't. So:

He (sing.) watches (sing.) the movie.

They (pl.) watch (pl.) the movie.

Then, you have to make sure your subject noun agrees with the main verb, regardless of modifiers in between the actual subject in the verb. So:

The boy climbing trees grows tall.

Trees grow tall.

In the first sentence, "boy" is the subject, and it's singular. That's why the verb has an -s at the end to match its singular subject. But in the second sentence, "trees" is the subject. That's more than one tree, so it's a plural subject that has to have a plural verb. So your verb doesn't have the -s at the end.