--- How _____ hours do you sleep a day?--- Well, about eight hours. But how _____ sleep do we students really need?

Look at the poster! There ______ a speech about Canadian culture in our school next Saturday.

What are ____________?

I hear a number of workers in the factory_____out of work.__Yes, and the number _____quite huge.

The population of China ________ 1.3 billion，and 80% of the population________farmers.