We received the following question from one of our readers:
We use the present continuous tense in a complex sentence when the subordinate clause begins with when and the whole sentence refers to the future.
Would it be incorrect to say: Before I watch TV, I’m doing my homework.
There are two answers:
1) If you are referring to the present, to what typically happens, then the answer is “NO”, it would not be correct. In this case, you would say “Before I watch TV (every night), I do my homework.”
2) If you are referring to the future, such as tomorrow or tonight, then the answer is “YES AND NO”. The possibilities are:
a) “Before I watch TV (tonight), I’m doing my homework.” or –
b) “Before I watch TV (tonight), I’m going to do my homework.” Notice that in this case we use the present continuous form ” ~ going (to)” + the base form of your main verb.
I hope this answers your questions.
The ESL Help! Desk