_______ the morning of March 31, she made an important decision in her life. [ ]

The man stood ____ the window, watching the boys playing outside. [ ]

What can we learn from Lei Feng? — We should not only think about , we should think about others as well.

Scientists say it may be five or six years ____ it is possible to test this medicine on human patients.

How much shall I pay for the telephone call? —You _____. It’s free.