21. — You’ve dropped ________ “s” in the word “necessary”.
— Oh, ________ letter “s” is doubled.
A. a; a B. a; the C. an; the D. the; the
22. —Don’t be late next time, Mike.
—____________.
A. No, I don’t B. Don’t worry C. Sorry, I won’t D. I don’t know
23. You’d better not always look up the new words ____________ the dictionary while reading. Sometimes we need to guess.
A. in B. on C. at D. from
24. _________ many children like KFC, I think they’d better try not to eat it too often.
A. Because B. When C. Although D. If
25. —Sally, could you go and help your father wash the car?
—Why ____________? I’m busy now. Amy is lying on the grass doing nothing.
A. me B. I C. him D. her