21. ___ Mr. Smith is waiting to see you. He appears to be quite ____ important person.
A. /; an B. A; an C. The; the D. The; /
22. ---How much shall I pay for the phone call? ----You ____ .This is free of charge.
A. shouldn’t B. can’t C. needn’t D. mustn’t
23. Who would you get ____ to the cinema with you?
A. gone B. to go C. going D. go
