vt.复制，复印，复写，(尤指不必要时)重复，再做一次
adj.完全一样的，复制的，副本的
n.完全一样的东西，复制品，副本

原形：duplicate第三人称单数：duplicates复数：duplicates过去式：duplicated过去分词：duplicated现在分词：duplicating

He duplicated his former mistakes.
他又犯了和以前一样的错误.
This is a duplicate.
这是一个副本。
Don't duplicate what you already do.
不要重复你已经在做的工作。
Is this a duplicate or the original?
这是副本还是正本？
This painting is a duplicate of the original artwork.
这幅画是原作的复制品。
She copied her friend's homework, but it was quickly detected as a duplicate.
她抄袭了朋友的作业，但很快被发现是重复的。
The hotel provided a duplicate key in case we lost our room key.
酒店提供了一把备用钥匙以防我们丢失房卡。
The library had a duplicate copy of the rare book, which was a relief for researchers.
图书馆有一本罕见书籍的副本，这让研究者松了一口气。
He ordered a duplicate of his birth certificate from the government office.
他从政府办公室订购了一份出生证明的副本。
A duplicate passport was issued to the traveler after their original one was damaged.
旅行者的护照损坏后，他们得到了一份副本。
The IT department made a duplicate of the database to ensure data security. (IT部门复制了数据库以保证数据安全。
She kept a duplicate set of house keys just in case.
她保留了一套备用钥匙以防万一。
The duplicate keys were found in the drawer where she always kept them.
那些备用钥匙被发现在她常放的地方抽屉里。
The software has a feature that allows users to create duplicate files for backup purposes.
该软件有一个功能，用户可以创建文件副本用于备份。