on the ball
成語所屬單字ball
on the ball — 慣用語
1. quick to notice, understand, or react to what is happening; alert and competent.
1.慣用語
釋義
機警；反應靈敏
quick to notice, understand, or react to what is happening; alert and competent.
例句
The new receptionist is really on the ball — she answers every email within minutes.
You need to be on the ball during the morning rush at the café.