back up
动词- To move backwards, especially for a vehicle to do so. · That beeping sound indicates that the truck is backing up.
- To move a vehicle backwards. · Back up the car a little, you're blocking the driveway.
- To undo one's actions. · I couldn't see how to finish the project, so I backed up and tried it another way.
- To reconsider one's thoughts. · This isn't working. Let's back up and think about it.
- To copy (data) so that it can be restored if the main copy is lost. · Back up your documents folder before applying the update.
- To provide support or the promise of support to. · You should be careful. This guy is backed up by the local gang.· When he said I wasn't there, I told him I was, and my buddy backed me up.
- For the non-striker to take a few steps down the pitch, in preparation to taking a run, just as the bowler bowls the ball.
- For a fielder to position himself behind the wicket (relative to a team-mate who is throwing the ball at the wicket) so as to stop the ball, and prevent overthrows.
在真实文章中学习back up
注册免费账号后，在图书馆中把鼠标悬停在任何单词上即可看到意思，还能听朗读、收藏单词并按你的记忆安排复习，看到每本书你已经认识多少。