Here's a breakdown:
* Pronouns are words that stand in for nouns. They can be singular or plural.
* Singular nouns refer to one person, place, or thing.
Examples:
* Noun: The cat is sleeping.
* Pronoun: It is sleeping.
* Noun: John is going to the store.
* Pronoun: He is going to the store.
* Noun: The tree is tall.
* Pronoun: It is tall.
Key point: The pronoun must agree with the noun it replaces in number (singular or plural) and gender (if applicable).