ph.
1. 支持，证实（某种说法）
If someone or something backs up a statement, they supply evidence to suggest that it is true.
2. 备份（文件）
If you back up a computer file, you make a copy of it which you can use if the original file is damaged or lost.
3. 将…付诸实施
If an idea or intention is backed up by action, action is taken to support or confirm it.
4. 支持（某人）
If you back someone up, you show your support for them.
5. 证实（某人）的说法
If you back someone up, you help them by confirming that what they are saying is true.
6. 倒车
If you back up, the car or other vehicle that you are driving moves back a short distance.
7. （车辆）堵塞，排成长龙
If vehicles back up, they form a line of traffic which has to wait before it can move on.
8. 倒行；退着走；后退
If you back up, you move backwards a short distance.
9. see also: backup
1. establish as valid or genuine
e.g. Can you back up your claims?
Synonym: back
2. become or cause to become obstructed
e.g. The leaves clog our drains in the Fall
The water pipe is backed up
Synonym: clogchoke offclog upcongestchokefoul
3. make a copy of (a computer file) especially for storage in another place as a security copy
e.g. You'd better back up these files!
4. move backwards from a certain position
e.g. The bully had to back down
5. give moral or psychological support, aid, or courage to
e.g. She supported him during the illness
Her children always backed her up
Synonym: support