21. Mary has _________ 18-year-old daughter who has ________ gift for singing.

     A. a; a     B. an; the    C. an; a     D. the; a

22. —___________ is the population of the United States?

   —I don't know exactly, but I'm sure that it has __________ population than China.

A. How much; much less      B. How many; fewer

     C. What; much less          D. What; a much smaller

23. It's far away from here and it's certainly not _____ walking distance.

     A. within    B. at     C. around     D. On

24. He _______ to act out the story he had read, but he

     failed.

A. deserved   B. tried      C. managed      D. pretended

25. In my opinion, the present situation ______ entirely

     new measures.

A. calls for   B. calls in      C. calls up    D. calls away

26. The plane ______, killing all 200 people aboard.