(三)已知两视图，补画第三视图。
参考答案：
女性初潮平均年龄为（）
A.10岁
B.11岁
C.12~14岁
D.15岁
E.16岁
We are all proud of the great changes in Beijing. We're sure Beijing will be even ________ tomorrow. [ ]
A. good
B. better
C. best
D. the best
