1) You need not write down the translation.
你不必写下译文。
2) You need not write to him.
你不必给他写信。
3) You needn't mince words in your speech.
你不必咬文嚼字。
4) You needn't erase the backboard after class.
课下你不必擦黑板
5) You needn't be alarmed.
你不必担忧。
6) You may spare yourself the trouble.
你不必费神。
参考词条