语法和词汇运用（共15小题：每小题1分，满分15分）
21. ----Dad, you see, a cell phone is so useful nowadays.
-----Absolutely. _______But it isn’t allowed in the classroom.
A. It’s up to you. B. That’s a good point.
C. How are you getting on? D. I didn’t get that.
22. It’s ______ most kind of you. Your support will certainly make ____ difference in our cause.
A. the, a B. 不填，a C. the, 不填 D.不填，不填
23. I’m sorry I can hardly follow you. Judging from your ________, you must be from the south.
A. tone B. look C. voice D. accent
