Coordinate adjectives describe the same noun independently. In a bright, cheerful room, both bright and cheerful describe room. A comma separates the two adjectives.
Two tests for coordinate adjectives
- Insert and. A bright and cheerful room keeps the intended meaning.
- Reverse the order. A cheerful, bright room gives the same two descriptions and still sounds natural.
These tests are clues. Read the phrase in context and ask whether each adjective describes the noun on its own. When you use a comma between coordinate adjectives, keep the final adjective next to the noun without another comma.
When adjectives build on each other
In a small green notebook, green notebook identifies the kind of notebook, and small describes it. This is the usual reading of cumulative adjectives. Write them together without a comma.
