The verb to undo · Conjugation
Future Simple of undo
The answer: will undo
A2
A decision made now, a promise or a prediction.
Quick answer
The Future Simple of the verb to undo is will undo.
Example: I will undo the knot tomorrow.
Full conjugation in the Future Simple
| Pronoun | Form | Contraction |
|---|---|---|
| I | will undo | I'll undo |
| You | will undo | You'll undo |
| He / She / It | will undo | He'll / She'll / It'll undo |
| We | will undo | We'll undo |
| You (pl.) | will undo | You'll undo |
| They | will undo | They'll undo |
Common mistakes to avoid
1. I will to undo ❌
After will, use the base form, with no to: I will undo. Will never takes -s, and the verb after it has no -s either. Say she will undo, not she wills undo or she will undoes.
2. I will can undo ❌
Will is a modal verb (a helper verb like can, must or should). Two modal verbs cannot go together. Use will be able to for can: I will be able to undo. Use will have to for must: I will have to undo.
3. When I will arrive, I will call you ❌
After when, if, before, after and as soon as, use the Present Simple for the future, not will. Say When I arrive, I will call you. Will goes in the other part of the sentence.
Practice quiz
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Frequently asked questions
How do you conjugate undo in the Future Simple?+
Use will + the base form (the verb with no to): will undo. The form is the same for every person: I will undo, she will undo, they will undo. In speech, will often becomes 'll: I'll undo.
When do you use the Future Simple of undo?+
Use will for a decision you make at the moment of speaking: The phone is ringing. I'll answer it. Also use it for a promise (I'll help you.) and for a prediction (I think it will rain.).
Is it will or going to?+
Use going to for a plan you made before you speak: I'm going to visit my grandma on Sunday. Use will for a decision you make now: I'm hungry. I'll make a sandwich. With undo: I'm going to undo (a plan), I'll undo (a decision now).
How do you make the negative of undo in the Future Simple?+
Use will not + the base form, or the short form won't: I won't undo, she won't undo. Careful with the spelling: the short form is won't, not willn't.
How do you make a question with undo in the Future Simple?+
Put will before the subject: Will you undo…?, When will she undo…? The main verb stays in the base form, with no -s and no to. Short answers: Yes, I will. / No, I won't.
Related pages: undo Future Simple
Pages on a similar topic or with a similar use, so you can keep exploring.
Updated on 12 November 2026 by the Big Challenge teaching team. Every year, more than 500,000 students across Europe take part in our English contest, created in 1999. Our teaching approach →
The Big Challenge · Updated on 12 November 2026 · Source: www.thebigchallenge.com/bl/academy/learn-english/verbs/undo/future-simple
© The Big Challenge. Copying allowed for classroom use. Every year, more than 500,000 students across Europe take part in our English contest, created in 1999.
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