I can________ be a nurse．I’m not a very patient person．

She ____________ as an animal trainer since 2003.

In America when you’re given a present, you can open it . You don’t have to wait.

Look! The light is still on. Is Mr Wu working in his office？—No, it _____ be Mr Wu. He has gone to Nanjing for a meeting.

Once a year, people take part in “_______ Lights” activity to help save energy.