backup 备份，替补，后援

　　Just admit it, you're a backup, she dosen't like you.

　　你就承认了吧，你只是一个备胎，她不喜欢你。

　　She is keeping you around just as a backup.

　　她把你留在身边，只是作为一个备胎。

　　疯狂练习吧！