back is up的意思

后退

back issue───過期報刊，過刊

backs up───v.支持，援助；（資料）備份；倒退；裱；堵車

back issues───過期刊物（backissue的復數）

back up───v.支持，援助；（資料）備份；倒退；裱；堵車

backed up───堵車了的；已備份的

backers-up───支持者

backing up───回投；封底焊

back injury───背部損傷

back focus───[攝]后焦點；反焦點；象方焦點

This often happens inadvertently when your back is up against a wall.───這一點常發生在我們面臨巨大困難的時候。

The trick is to pick the animal up by the back of its neck.───竅門在于抓住動物的后脖頸把它提起來。

Your dress is rucked up at the back.───你的連衣裙后面起褶兒了。