more, and you will improve your spoken English.
A：To speak
B：Speaks
C：Speak
D：Speaking
圆C1：x2+y2+4x+4y+4=0与圆C2：x2+y2﹣4x﹣2y﹣4=0公切线条数为（ ）
China is famous _____ the Great Wall.
