1 . —Mom, who won the first place in the TV show I' m a singer?
—It ________ be Han Hong, but I' m not sure. Last Friday I missed it.

A．might

B．must

C．should

2 . --- Where is Jack? I can’t find him anywhere.
--- He ______ his homework upstairs.

A．might have done

B．must have done

C．might be doing

D．must do

3 . Coughing _____ also be used for social reasons, such as the coughing before giving a speech．

A．may

B．should

C．must

D．need

4 . —Do you think he will do me a favor?
— As far as I know, he is the last one to help others. He______be prepared to give you a hand, though.

A．might

B．must

C．can

D．should