in writingWRITEif you get something in writing, it is official proof of an agreement, promise etc 〔协议、诺言等〕以书面形式 Could you put that in writing, please? 请你把它写下来好吗?
in writing• You should have asked them to put what they agreed in writing.• I don't have anything in writing, but they said they expected me to start work Monday.• Please confirm in writing the date you intend to leave.
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