名詞 back up:

1. an accumulation caused by clogging or a stoppage
   同義詞：backup
2. someone who takes the place of another (as when things get dangerous or difficult)
   同義詞：stand-in, substitute, relief, reliever, backup, backup man, fill-in
3. a subordinate musical part; provides background for more important parts
   同義詞：accompaniment, musical accompaniment, backup, support
4. (computer science) a copy of a file or directory on a separate storage device
   同義詞：backup, computer backup
5. the act of providing approval and support
   同義詞：backing, backup, championship, patronage

動詞 back up:

1. give moral or psychological support, aid, or courage to
   同義詞：support
2. move backwards from a certain position
   同義詞：back off, back down
3. establish as valid or genuine
   同義詞：back
4. make a copy of (a computer file) especially for storage in another place as a security copy
5. become or cause to become obstructed
   同義詞：clog, choke off, clog up, congest, choke, foul

1. His condescending attitude really gets my back up.
   他那種居高臨下的恩賜態(tài)度實在使我很生氣。
2. He drought along a file of document to back up his claim.
   他隨身攜帶一卷宗文件以便證實索賠要求。
3. 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年這個期限臨近了，最初支持平等權(quán)利修正案的一些州后來改變了主意，投票反對這個法案。
4. The bus had to back up and turn around.
   汽車得往后退，再倒過來。