1.支持，撑腰

2.倒车

3.证实

4.淤塞

同义词：back down，back off;

support;back;congest，foul，choke，choke off，clog，clog up。

反义词：unclog。

back up的英语解释：

move backwards from a certain position

give moral or psychological support, aid, or courage to

establish as valid or genuine

become or cause to become obstructed

make a copy of (a computer file) especially for storage in another place as a security copy

相关短语：

a back answer n.顶嘴

a back issue n.过期期刊

a back number n.过期的刊物,过时的人

a pat on the back 鼓励,赞许

a slap on the back 鼓励,促进,赞扬

a stab in the back n. 诽谤,伤人的暗箭

answer back 回嘴,顶嘴;给…回电话

arch one’s back 拱起脊背

as bare as the back of one’s hand 一无所有,一贫如洗

at sb.’s back adv.支持某人

back up的例句：

1.He doesn’t have his heart in the right place. He would find every opportunity to stab in the Back of others.

他的心术不正,动不动就在别人的背后捅刀子。

2.Misers put their Back and their belly into their pockets.

爱财如命。

3.What is got over the devil’s back is spent under his belly.

(钱财)来得不正,去得也不正。

4.All the treasures of the earth would not Bring Back one lost moment.

机会失去不再来,千贯万贯难赎回。

5.They rolled up the money and left through the Back gate in a tearing hurry.

他们十分仓促地卷起钱就从后门逃走了。