中国最早的自然保护区是_______。
A．广东鼎湖山
B．福建金顶山
C．四川鼎湖山
D．云南明鼎山
参考答案：A
将下面的句子重新排列，组成对话。
( ) Really? What's he like?
( 4 ) Is he quite?
( 1 ) I have a new math teacher.
( ) Great! He can play with us. Is he strict?
( ) No, he isn't. He's very active.
( ) He's young and strong. He's a university student.
( ) Yes, he is. But he's very kind.
机翼结构的主要承力结构是（）
A、蒙皮
B、翼梁
C、翼肋
D、桁条
