Certified English teacher and language coach

We cannot use will in time clauses with when, as soon as, after, before, until. We use a present tense to talk about the future in this case. In the main clause we use a will-future.

This is very similar to the First Conditional.

e.g.#1: I will call you when I get home.

e.g.#2: I’m not helping you until I know the reason.

e.g.#3: He’ll bring me my coffee as soon as he finishes the call.

Remember: do not use a negative after until

Time and If-Clauses

There is a difference between when and if in English.

if: expresses a condition, there is a possibility that something will happen, but it is not certain.

when: the speaker is certain that something will happen, the question is only when.

e.g.#1: I will call you when I get home.  (It is very certain that I will get home, the question is only when.)

e.g.#2: I will go walking if the weather is nice.  (I’m not sure what the weather will be like but in case it’s nice, I will go walking.)