I _____ sooner but I didn’t know that they were waiting for me .
______ the chairman of the council, the vice chairman does duty for him.
In the competition to be held, a gold medal, together with a certain sum of money, _____ the champion.
You can only be sure of _____ you have at present; you cannot be sure of something _____ you might get in the future.
The traditional view is _____ we sleep because our brain is “programmed” to make us do so.
We arranged to meet at the cinema at 7:30, but he failed to ______.