1、get down

使沮丧；使忧郁

At times when my work gets me down, I like to fantasize about being a farmer.

有时当工作让我沮丧时，我喜欢幻想自己是一个农场主。

写下；记下

The idea has been going around in my head for quite a while and now I am getting it down on paper.

这个想法在我脑海里萦绕许久了，我现在就将它写在纸上。

俯身；跪下；趴下

She got down on her hands and knees on the floor.

她双手撑地跪在地上。

'Get down!' she yelled. 'Somebody's shooting!'

“趴下！”她大声喊道，“有人开枪！”

2、back up

支持，证实（某种说法）

Radio signals received from the galaxy's centre back up the black hole theory.

从该星系中心收到的无线电信号证实了黑洞理论。

Her views are backed up by a 1989 Home Office report on crime.

1989年内政部的一份犯罪报告印证了她的观点。

备份（文件）

Make a point of backing up your files at regular intervals.

一定要定期备份文件。

I get so annoyed when I lose work because I've forgotten to back it up.

当我因为忘了备份把完成的工作弄丢时，真是懊恼极了。

将…付诸实施

The Secretary General says the declaration must now be backed up by concrete and effective actions.

秘书长说现在必须将宣言付诸具体有效的行动。

It is time the Government backed up its advert campaigns with tougher measures.

是政府采取更严厉的措施来兑现其宣传承诺的时候了。