have a ball
例:I really had a ball at your party.
The little ones had a ball in the park the whole afternoon.
The ball is in your court.
用：指采取行动等。your可换成his, her, their, Jack's等人称。
例 :Now you know everything. The ball is in your court. Are you going to dismiss him or give him another chance?
.Well, that's all I know about the matter. Now the ball is in your court, Bi11.