You should make a copy of the disk as a backup.

你应该将磁盘复制一个备份。

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youdao

youdao

In the late 1980s, Jon was hired as a backup singer for pop superstar Gloria Estefan.

VOA: standard.2010.04.02

You really need that because if you have only one copy of something, you don't have a backup; so, you can store the one copy separately.

你真的很需要这项发明,因为要是你只有一份的话，你就没有备份;,这样的话，你就可以将副本单独留存。

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So it's like a backup.

所以，这就像是备用。

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Maybe it'll be broadband, but then there's a backup for 3G connection or 4G, right?

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That radio you refer to is actually a backup plan that is almost never used.

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