back up

vi. (因积聚而)拥堵, 堵塞
vt. 支持, 援助, 倒退, （资料）备份

例句与用法：

His condescending attitude really gets my back up.

他那种居高临下的恩赐态度实在使我很生气。

He drought along a file of document to back up his claim.

他随身携带一卷宗文件以便证实索赔要求。

As the1979 deadline came nearer, some states which at first had backed up the Equal Right Amendment changed their mind and voted against it.

1979年这个期限临近了，最初支持平等权利修正案的一些州后来改变了主意，投票反对这个法案。

The bus had to back up and turn around.

汽车得往后退，再倒过来。

详细释义：

支持

He would have lost his position if you hadn't backed him up.

假如你当初没有支持他, 他可能已经失去职位了。