拳击手每天早上都会对着镜子空击练习15分钟。

The boxer practices ___shadowboxing in front of a mirror for 15 minutes every morning.

他在面试前反复练习回答可能遇到的问题，就像在打空拳一样。

He kept practicing answers to potential questions before the interview, like ___shadowboxing with his thoughts.