let／blow off steam
1．let or make steam escape 排气；放气
The worker let off some steam because the pressure was too high．那位工人排出一些水气，因为压力大高。
2．get rid of physical energy or strong feeling through activity；in dulge in strong or violent language to relieve one's feeling 发泄精力或情绪；讲激烈而粗野的话以发泄感情；出气
When the rain stopped，the boys let off steam with a ball game．雨停后，孩子们赛球解闷。
When men let off steam，they tend to shout；women，on the other hand，express their feelings by weeping．男人发泄强烈感情时，倾向于大声喊叫；妇女则不然，用哭泣来发泄感情。
Don't take any notice of what he says；he's just letting off steam．不要理睬他所说的话，他在出气罢了。
Bill had to take his foreman's rough criticisms all day and he would blow off steam at home by scolding the children．比尔整天挨领班的训责，回家后就拿孩子出气。