问题
_____ do you practice _____ tennis? —Twice a week.[ ]
A: How long, play
B: How farIMG style="WIDTH: 1px; HEIGHT: 1px; VERTI
C: How many times, playing
D: How often, playing
B: How farIMG style="WIDTH: 1px; HEIGHT: 1px; VERTI
C: How many times, playing
D: How often, playing
正确答案是：
