题目

Steve isn’t as  ______ as Kelly. He often makes mistakes(错误) in his writing. A. interesting       B. tidy               C. careful          D. difficult 答案：C 请依据右图指出男女性主要性器官的发育开始突增的年龄分别是（ 　）A．9-10岁和10-11岁B．13-14岁和9-10岁C．9-10岁和13-14岁D．10-11岁和9-10岁