This rule comes first because understanding it can help you understand some of the others. In most sentences you follow it
naturally, but it can cause trouble. The rule is as follows: The subject and verb of each clause must agree in number.
If you have a singular subject, you need a singular verb. If you have a pluralsubject, you need a plural verb. Singular and plural tell how many. Singular means one. Plural means more than one. Both your subject and verb must give the same signal as to how many you are talking about.
Read the following sentences and see if you can find any problems with subject/verb agreement.
1. The cat come home tired.
2. The cat comes home tired.
3. The cats come home tired.
Can you explain the problem in sentences one and four? If not, consider that with most nouns, our language forms the plural by adding an s, but with verbs, an s is added only in the third person singular.
Singular Plural 1st person I come we come 2nd person you come you come 3rd person* he, she, it, this, or that comesthe cat* comes they, these, or those comethe cats* come*All nouns—words such as table, cat or frog—should be considered 3rd person.