II. 单项选择 (20分,每小题1分)
21. Mrs. White isn’t here. She ___B___ London.
A. has been to B. has gone to C. went to D. has gone
22. One-child policy has __D____ controlling China’s population.
A. did well in B. been good at
C. worked good in D. worked well in
23. In our class, about ___D___ of the students are girls.
A. three fifth B. third fifth C. third fifths D. three fifths
24. The weather in summer here is cooler than ___B___ in Beijing.
A. this