you ___tell him about it.because he has know it.要用mustn't 还是needn't

问题描述:

you ___tell him about it.because he has know it.要用mustn't 还是needn't

needn't 只是没有必要,因为他已经知道了。
mustn't 表示强烈的禁止,不准,语气强烈,用在这儿不恰当

是needn't

needn"t

you needn't___tell him about it.because he has know it.
你不需要告诉他,因为他已经知道了
needn't 不需要
mustn't 禁止

needn't
他已经知道了,你不必告诉他了.
mustn't是不可以