before-hand事前
before-hand maintenance预知维修
know before hand预知
break before hand先断后通
Before Folding His Hand前折把手
Before Hand After Hand过手前后
before hand withdrawal of gas预抽瓦斯
Hand before用手遮住
Just use hand before只是用手遮住
ADV（副词） If you do something beforehand, you do it earlier than a particular event. 事先; 预先
How could she tell beforehand that I was going to go out?
她如何预先知道我将出门的？