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- Future tense in conditional clauses 5 answers
Should I say:
When I am 18, I'll take my driving test
When I'll be 18, I'll take my driving test
Which one is the correct sentence?
Although both clauses imply future tense, "will" is not used in the clause starting by "when". Then the first sentence is correct, the second is not.
English has no future tense, but can express the future in several different ways. Will (or, in speech, ’ll) + the plain form of the main verb is one of them and is typically used to make a prediction or to express a decision about the immediate a future. For this reason, it is clearly not appropriate in your example.
Another way in which English expresses the future is by using the present tense, and this is typically used to talk about future certainties. In the example, the speaker thinks that being 18 one day is a certainty, and that is why the present tense is used.
Of the two sentences asked about, the first is correct and the second is incorrect.
You can also say "When I turn 18, I'll take my driving test".
You don't need "will" in both clauses, only the main clause (the second one in all these cases).
If 'when' is used to indicate a context in the future, the 'will' becomes redundant and 'when' is followed by the present form of whatever verb.
In this case: when + subject + present simple , subject + future simple
When I know the answer, I'll call you
When he leaves for work, I'll telephone.