—Your room is very untidy. Please________ your things, Mike.—OK, Mum. I will do it at once.
-Help yourself to some more meat. -_______________.
-Do you need my help, Mary? -_____________.
-Hello, Jack. How are you doing? -__________.
-When was David born? -He was born ________ June 12, 1989.
Because the old people ________ about thirty percent of the population, we should care more about them.