David doesn’t give up _______ he has failed in the experiment four times.

There is going to ________a sports meeting next week. If it ________, we’ll have to cancel it.

I hate travelling by air_______ you usually have to wait for hours before the plane takes off.

The dress fits me well,       I don’t want to buy it because it’s too expensive.

— ______ are you going to be an actor?—I’m going to take acting lessons.