the calm before the storm“暴风雨前的平静”。这个习语通常指重大活动、激烈辩论或者灾难发生之前的平静。

【例句】
The hall was very quiet, but it was the calm before the storm.
大厅里一片安静，但这是暴风雨前的平静。

He can prepare his lessons and enjoy the calm before the storm!
他可以备课，享受暴风雨前的平静！