* Adjectives describe nouns.
* Pronouns replace nouns.
* Nouns are words that name people, places, things, or ideas.
Here are some examples:
* The pale moon shone brightly in the sky. (Pale describes the noun "moon")
* She was pale from the heat. (She is a pronoun that replaces a noun, like "woman")
* The color pale is often associated with illness. (Pale is used as a noun here, but it's still derived from the adjective.)