English grammar rule Comma compound sentence

When personal pronouns serve as subjects of a sentence or clause, they are in the first (I, we), second (you), or third person (he, she, it, they). They also are either singular (I, you, he, she, it) or plural (we, you, they). You must use the verb form that corresponds with your pronoun in the same sentence.

Examples of 'Comma compound sentence' rule

Incorrect	They loves a white beach.
Correct	They love a white beach.
Incorrect	He enjoy dinner when it come to the table.
Correct	He enjoys dinner when it comes to the table.