When to use the -s (or -es) form of a present-tense verb

Figure. Flowchart. If you aren't sure whether to use the -s (or -es) form of a present-tense verb, first ask: Is the verb's subject he, she, it, or one? If yes, use the -s form (loves, tries, has, does).  If the verb's subject is not he, she, it, or one, ask: Is the subject a singular noun (such as parent)? If yes, use the -s form.  If no, ask: Is the subject a singular indefinite pronoun -- anybody, anyone, each, either, everybody, everyone, everything, neither, no one, soemone, or something?  If yes, use the -s form.  If no, use the base form of the verb (such as love, try, have, do).