* Common Nouns: These are the names of general things, places, or people (e.g., cat, city, teacher). They can act as the subject (who or what is performing the action) or the object (who or what is receiving the action).
* Pronouns: These words replace nouns to avoid repetition (e.g., he, she, it, they, we). They also act as subjects or objects.
Examples:
* The cat (common noun as subject) sat on the mat.
* He (pronoun as subject) played with the ball.
* The children (common noun as subject) gave her (pronoun as object) a gift.
In short, both common nouns and pronouns can be used in various positions within a sentence, depending on their function. There's no fixed rule that one always comes before the other.