A:①②③
B:①②④
C:①③④
D:②③④
—Oh. Mary's not here these days. Is she ill? —_____.Her mother told me that she was in hospital.
下列穿过澳大利亚的一条特殊纬线是( )
不考虑地形、海陆,两人从南极同时以相同速度出发,分别沿40°E和20°W向北行进,产生的情况是( )