A SINGULAR subject takes a singular verb. A PLURAL subject takes a plural verb.

A singular verb are verbs that commonly end in -s.
Example sentence:
Jane (singular subject) takes (singular verb) the book from her bag.

Example sentence : (for a plural subject)
They (plural subject) are (plural verb) cheering for their favorite team.

Note: the word 'is' is a verb. it's plural form is 'are'.