C 完全一样的东西，复制品one of two or more thing that are exactly alike; copy

　keep a ～　保留副本
　in ～　一式两份
　～ of　完全一样

　Is this a duplicate or the original?　这是副本，还是正本?
　Your jacket's a duplicate of mine.　你的夹克跟我的一样。
　This form should be filled out in duplicate.　这种表格要填写一式两份。

1. vt.复制　 double, multiply by two
2. vt.复印　 be〔make〕 exact copy of

　～ document　复印文件
　～ key　配钥匙

　Can you duplicate the key for me?　你能把这把钥匙再给我配一把吗?
　The manager asks the secretary to duplicate the document.　经理让秘书复印这份文件。
　It occurred to us that we were merely duplicating their research.　我们想到我们仅仅在重复他们的研究。
　The document was duplicated.　文件复制了。
　The record-breaking harvest of 1975 may not be duplicated this year.　今年不可能再获得1975年那种创纪录的丰收。
　All members received duplicated notices of the meetings.　所有与会人员都收到了会议通知的复印件。

　［词源］拉丁语duplicare（加倍）