be a law unto himself/herself etcINDEPENDENT PERSONto behave in an independent way and not worry about the usual rules of behaviour or what other people do or think 我行我素,自行其是 Boys his age are a law unto themselves. 他这个年龄的男孩都是我行我素。
be a law unto himself/herself etc• She was a law unto herself and did what she wanted to do.
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