Question

insert one comma to separate the coordinate adjectives.
the frustrated overwhelmed writer sat at his antique mahogany desk for hours attempting to complete the final draft of his novel.

Explanation:

Step1: Identify coordinate adjectives

Coordinate adjectives are adjectives that modify the same noun and can be separated by "and" or a comma. Here, "frustrated" and "overwhelmed" both modify "writer" and are coordinate.

Step2: Insert comma

Place a comma between "frustrated" and "overwhelmed".

Answer:

The frustrated, overwhelmed writer sat at his antique mahogany desk for hours attempting to complete the final draft of his novel.