--All the building materials have been washed away.---So I have heard. But there was no sign ______ a heavy rain was on the way last night.
There used to be a temple in your village,________?
The new bridge is ________ the one built last year.
________knowledge a man has,________it is for him to get a good job.
Many chemical substances react________oxygen.
The population of China ________ 1.3 billion,and 80% of the population________farmers.