21. As we can see, the prices of vegetables _____ according to the season.
A. vary B. fall C. rise D. swing
22. The bridge over the canal is 1, 000 meters ____ length.
A. with B. in C. at D. on
23. As _____ tourist attraction, the Great Wall does have _____ strong attraction to visitors from home and abroad.
A. the; 不填 B. the; a C. a; 不填 D. a; the
24. The girl refused your offer last time. _________ you don't want to talk to her.
A. No wonder B. No doubt
C. Above all D. After all
25. —Have you heard of this new computer brand, Mike?
—Yes, of course and I've decided to buy ________.
A. it B. one C. this D. that
