While has three different functions when it is used as a conjunction. It can:
- refer to time
- express contrast
- be a synonym for although.
|While shows us that something happens at the same time something else is happening.
I fell asleep while I was watching television.
(= 'I fell asleep in the middle of watching television.')
It didn't rain at all while we were on holiday.
(= 'It didn't rain during our holiday.')
|We use while with the present continuous and past continuous tenses to show longer actions which are interrupted:
It started raining while I was waiting for the bus. (past continuous)
The phone always rings while I'm having a shower. (present continuous)
|We also use while with the present simple and past simple tenses:
My wife walked the dog while I washed the car. [past simple]
I'll tidy the house while you are at work. [present simple]
Be careful – we do not use will after while when speaking about the future:
I'll tidy the house while you will be at work.