13. John _______ go there with us tonight, but he isn’t very sure about it.
A must B can C will D may
14. Sandra didn’t come to school today. I think she _______ be ill.
A shall B can C must D should
15. Cars and buses _______ stop when the traffic lights turn red.
A can B need C may D must
16. —Is Mr. Huang in the classroom?
—No, he _______ be there. He is waiting for me at the school gate.
A mustn’t B may not C can’t D isn’t able to
17. —Can you write letters in English now? —No, I _______.
A may not B mustn’t C needn’t D can’t
18. —Can you answer my question? —Sorry, I _______. I know _______ about it.