A:how was it
B:what was it that
C:when was that
D:when was it that
若a=sin2,b=cos2,则a,b的大小为( )
同纬度夏季陆地气温 ____ 海洋,冬季陆地气温 ____ 海洋;海拔越高气温越____
为了促进欧洲西部的经济发展,该地区形成了一个区域性的国际组织是 ( )
下列现象是地球公转造成的是( )