--What shall we do tonight then?--________ --whatever you want.
Many chemical substances react________oxygen.
The population of China ________ 1.3 billion,and 80% of the population________farmers.
They are quite different ________ each other ________their tastes.
He ________to come at eight, but in fact he never comes before nine.
Mr. Smith is ________a teacher. He is also our good friend.