从 A、B、C、D 四个选项中，选出可以填入空白处的最佳选项，并在答题卡上将该项涂黑。
21. As we all know, apples are sold by ______ weight, and socks are sold by _______ dozen.
A. the; a B. /; a C. /; the D. the; the
22. —I’m afraid I have to leave for Miami tomorrow.
— __________.
A. I’m afraid not. B. Have a good journey. C. Please do. D. Can’t you stay a bit longer?
23. — Do you think our team played very well yesterday?
— _________.
A. They were not nervous at all B. They were still young
C. They played worse. D. They couldn’t have done better
24. ________ seen my niece for ages, I couldn’t recognize her at the moment.
A. Having not B. Having never C. Not having D. Never having
25. Word comes that some free souvenirs(纪念品) will be given to _______
