I backed up carefully until I felt the wall against my back.

我小心翼翼地后退了几步，直到感觉到后背贴上了墙。

《柯林斯英汉双解大词典》

I backed up a foot and my attacker stopped attacking me.

我后退一步，攻击者停止了攻击。

youdao

I backed up and went the other direction, to be honest with you.

诚实地说我换方向退后了。

youdao

And Rutherford, who I have already described to you as being a little bit colorful in his language, backed up Bohr on this.

而卢瑟福，就是以前我跟你们提过的那个,语言丰富生动的人，在这一点上证实了波尔的理论。

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The same would have been true had I backed up to iCloud instead.

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"Obviously, the competitive edge doesn't want to give up any hits or runs or anything like that, but at the same time it's throwing some pitches I wouldn't throw in certain counts and I think in the third inning I kind of backed up some changeups there, " Harvey said.

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