【单选题】The teacher ______ his fingers on the desk impatiently while waiting for the student's answer.
【简答题】adv. impatiently; becoming difficult to control. (r)
【简答题】adv. impatiently; becoming diffult to control
【简答题】r__________ adv. impatiently; becoming difficult to control
【简答题】__________adv. impatiently; becoming difficult to control