—Is that Tom in the teachers' office?--No, it ________ be him. He's gone to the hospital.
--“Oh, no!There isn’t any sugar left. -- ______. I’ll buy some when I go into town.
You can’t imagine(想像) how much difficulty he had ___________his bad moods.
Amy was not sure _______________________.
When I feel blue , I prefer ________some books _______myself up.
The sign ______, “ No photos!” Why are you still taking photos here ?