undo
Base form
undo
/ʌnˈduː/
Past simple
undid
/ʌnˈdɪd/
Past participle
undone
/ʌnˈdʌn/
MeaningB2
to open something tied or fastened; to cancel the effect of something
what’s done cannot be undone
In use
- Question · Form 1Can you undo this knot for me?
- Imperative · Form 1Undo your seat belt only when the plane stops.
- Past simple · Form 2Yesterday Ben undid all my hard work in five minutes.
- Past simple · Form 2Last night I undid the top button of my shirt because it was so hot.
- Present perfect · Form 3I’ve undone the last change, so the file is back to normal.
- Passive · Form 3The damage to the old building can’t be undone.
Watch out
Undid and undone come from did and done: undoed and undidded are wrong. Your shoelace is undone means untied.
Irregular VerbsLearn all three forms for good
Short lessons by frequency or by pattern, audio for every form and daily reviews that bring back exactly the verbs you are about to forget.
Install on your phoneScan with your phone camera to download the app