21. If the president had visited the hospital this morning, it ________ the headline in tomorrow's paper.
A．will be B．could be C．had been D．was
22. — Is it convenient if I call you up at 9 tomorrow morning?
— I am afraid not. I _____ a group of visiting teachers then.
A. am meeting B. will meet C. will be meeting D. will have met
23. I couldn’t help appauding for Liu Xiang’s excellent performance ______he got the first prize on the stage in the 16th Asian Games.
A. for another time B. suddenly C. the moment D. once
