time clauses take present, never will (GiU Unit 25)
The frame
Section titled “The frame”Come and see us the next time you are in London. ✓
Time clause + future idea → present tense. The will lives only in the main clause:
- ✗ the next time you will be in London
- ✓ I’ll call you when I get home (✗ when I will get)
- ✓ We’ll go out after it stops raining
- ✓ As soon as the taxi arrives, we’ll leave
- ✓ I’ll wait until you finish
The trigger words
Section titled “The trigger words”when, after, before, until, till, as soon as, while, the next time, once, by the time
Present perfect also allowed for emphasis (Unit 25: when I’ve done):
- ✓ I’ll phone you when I’ve finished (= when I finish — emphasis on completion)
| clause | tense |
|---|---|
| time clause (when/until/…) | present / present perfect — never will |
| main clause | will / imperative / going to |
Future-idea test: does the clause express when something happens? → present even if it’s about tomorrow.
Source
Section titled “Source”Raymond Murphy, English Grammar in Use, Unit 25 — when I do / when I’ve done. Ebot lesson 2026-09-05.