A:向上排空气法
B:排水集气法
C:向下排空气法或排水集气法
D:排空气法,排水集气法都可以
There are some ____ (woman) over there.
“a=2”是“函数f(x)=x2+2ax﹣2在区间(﹣∞,﹣2内单调递减”的( )
—Were you at home yesterday?
—No, I________. I was ________ school.