undo

verb

/ʌnˈduː/

动词形式

present simple I / you / we / they undo	/ʌnˈduː/ /ʌnˈduː/
he / she / it undoes	/ʌnˈdʌz/ /ʌnˈdʌz/
past simple undid	/ʌnˈdɪd/ /ʌnˈdɪd/
past participle undone	/ʌnˈdʌn/ /ʌnˈdʌn/
-ing form undoing	/ʌnˈduːɪŋ/ /ʌnˈduːɪŋ/

undo something to open something that is fastened, tied or wrapped打开；解开；拆开
- to undo a button/knot/zip解开钮扣/结/拉链
- to undo a jacket/shirt解开夹克/衬衫
- I undid the package and took out the books.我打开包裹取出书来。
opposite do up
undo something to cancel the effect of something消除，取消，废止（某事的影响）
- He undid most of the good work of the previous manager.他把前任经理的大部分功绩都毁掉了。
- It's not too late to try and undo some of the damage.想办法补救部分损失还为时不晚。
- UNDO (= a command on a computer that cancels the previous action)撤销（计算机的还原指令）
- Just select ‘Edit’ and ‘Undo’ to cancel the previous action.只要选择“编辑”和“复原”便可撤销前一个动作。
[usually passive] undo somebody/something (formal) to make somebody/something fail打败；挫败
- The team was undone by the speed and strength of their opponents.这个队伍被对手的速度和力量打败了。
Topics Difficulty and failurec2

词源Old English undōn (see un-, do1).