紧急避孕需男女在发生性行为后（）小时内服用药物。
A.12小时
B.24小时
C.48小时
D.72小时
参考答案：D
______has Mr. White been a member of Greener China since he ______ to China?[ ]
A. How soon, comes
B. How often, got
C. How long, came
D. How far, arrived
