Answer:
1.Pronouns are words that are used to take the place of nouns in sentences. They usually refer back to a noun used earlier in the sentence, and they must match the number, point of view, and gender of the noun. We use pronouns to make sentences clearer, less awkward, and smoother.
2.Reflexive pronouns are words like myself, yourself, himself, herself, itself, ourselves, yourselves and themselves. They refer back to a person or thing. We often use reflexive pronouns when the subject and the object of a verb are the same. I cut myself when I was making dinner last night.
3.This, if a subject is singular, its verb must also be singular; if a subject is plural, its verb must also be plural. In the present tense, nouns and verbs form plurals in opposite ways: nouns ADD an s to the singular form; verbs REMOVE the s from the singular form.