1. undo的动词过去分词

a.[F]

1. 没有做的，未完成的
   I left my work undone.

   工作未完成，我就放下了。

2. 毁了的；丢脸的
3. 烦乱的；扰乱的
4. 解开的；松开的
   His bow tie had come undone.

   他的领结松开了。

adj.

1. not tied or fastened.
2. not done or finished.
3. formal or humorous ruined by a disastrous setback.