How often do you play sports? Three times a week.你多久做一次运动？一周三次。
点拨：____ 多久一次，用来提问动作发生的频率。回答用：everyday, once a week, twice a month等词语。
____多长，用来询问多长时间，也可询问某物有多长。
How long does it take to get to Shanghai from here? How long is the ruler?
____多远， 用来询问距离，指路程的远近。
How far is it from here to the park? It's about 2 kilometers.
