—Did that sportsman win ____ gold medal at ____Athens Olympics?

—Yes, he did.[ ]

A. a; an    

B. a; the      

C. a; /    

D. /; the

寒潮所带来的强冷空气主要来自于[ ]

A．青藏高原

B．新疆

C．蒙古、西伯利亚地区

D．北冰洋