--- Is Tina a shy girl?         

--- Yes, she is always afraid of ______ in front of her classmates.

A．giving

B．give a speech

C．give a speaking

D．giving a speech

北冰洋和南极洲的共同点是[ ]

A．跨纬度最广

B．纬度最高

C．地势最高

D．地势最低平