A:点P在线段AB上
B:点P在线段AB的反向延长线上
C:点P在线段AB的延长线上
D:点P不在直线AB上
As we know, his father is a very famous scientist in physics. But what you don't know is that he _______ as a farmer for five years.
①气候变化 ②人类活动 ③地壳的变动 ④ 海平面的升降
下列各句中,划线的成语使用恰当的一项是( )