Change, as a bill

AMEND

["Think of what you might do to a written proposal to improve it."]

"Change, as a bill" hints at modifying something official, like a proposed law. The word "bill" here refers to legislation, not money, and "change" suggests altering it—which is exactly what "amend" means. The clue plays on the double meaning of "bill" but leans toward the legal sense, making "amend" the perfect fit.