Remove, as pencil marks

ERASE

Think of what you might do to a mistake on paper before starting over.

"Remove, as pencil marks" is a straightforward definition clue pointing to the action of getting rid of something written in pencil. The answer "ERASE" fits perfectly because it’s the common word for rubbing out pencil marks, whether with an eraser or another method. There’s no hidden wordplay here—just a direct match between the clue’s meaning and the answer. Think of how you’d fix a mistake in a notebook, and "erase" is the natural choice.