问题补充:
— do you go to the zoo with your brother?
—Three times a month.
A. How long
B. How often
C. How old
D. How much
答案:
A. How long
(答案→)B. How often
C. How old
D. How much
解析:句意:--你和你的弟弟多长时间去一次动物园?--一个月三次。A. How long多长;B. How often多久一次;C. How old多大; D. How much多少。根据答语可知这里回答的是表示频率的词,根据句意故选B。