My brother exercises （for times a week）对括号里提问

网友回答

How often does your brother exercise?
你弟弟多久锻炼一次?
how often 多久一次
======以下答案可供参考======
供参考答案1:
How often does your(my) brother exercise?
How often 问的是频率
供参考答案2:
How often does your brother exercise?
供参考答案3:
应该是four
How often does your brother exercise？你兄弟多久锻炼一次
这里是对频率提问，所以用how often