Pronouns take the place of nouns. Personal pronouns have what is called case. Case means that a different form of a pronoun is used for different parts of the sentence. There are three cases: nominative, objective, and possessive.
Nominative case pronouns are I, she, he, we, they, and who. They are used as subjects, predicate nominatives, and appositives when used with a subject or predicate nominative.
Objective case pronouns are me, her, him, us, them, and whom. They are used as direct objects, indirect objects, objects of the preposition, and appositives when used with one of the objects. You and it are both nominative and objective case. Possessive case pronouns are my, mine, your, yours, his, her, hers, its, our, ours, your, yours, their and theirs. They are used to show ownership.
Possessive pronouns never have apostrophes, but possessive nouns do. Do not confuse the possessive personal pronouns its, your, and theirwith the contractions it's (it is, it has), you're (you are), andthey're (they are).
Instructions: Choose the correct form of the pronoun.
1. Our dog wagged (its, it's) tail for dinner.
2. (Your, You're) answer is right.
3. (Its, It's) been foggy all week.
4. This is (their, they're) first win.
5. (Your, You're) here on time!
--For answers scroll down.
3. it's (it has)
5. you're (you are)
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from Daily Grammar Lessons Blog