A:could I do
B:could I have done
C:should I do
D:must I have done
Mr. King is _______ teacher I've met.
如图反映了对降水的影响因素是( )
如图,在平面直角坐标系中,矩形OABC的对角线OB,AC相交于点D,且BE∥AC,AE∥OB,
There is _______ corn in the house.