let your hair down

　　放松，放松一下

　　释义：

　　(informal) to relax and enjoy yourself, especially in a lively way 放松;轻松一下

　　例句：

　　It is only with friends that most people feel they can let their hair down and be themselves.

　　The office party is a great chance to let your hair down, get to know your colleagues better and enjoy a drink on your employer's dime – in theory.