In our city, _______ middle school students want to work as a teacher in the future.

We were told that Mr Green _____ the office for a few minutes when we arrived.

Who is the man _______ your father is talking to? [ ]

Some people fear that ______ air pollution may bring about changes in ______ weather around the world.

The light in his room is still on. Do you know _________?— To prepare for the coming exam, I think.