Is "at" necessary from the phrase "chuff at her"?
Native speaker’s answer
Rebecca
"At" is necessary here because the action (chuffing) is being directed at someone. Similar to "laughing at her" or "screaming at John," which involve the preposition "at" to indicate who the action is being directed at, "chuffing at her" also requires a preposition. Ex: Don't laugh at her. She's embarrassed. Ex: I am mad at my brother for breaking my laptop.