一周锻炼两次 exercise twice a week

我一周锻炼两次 I exercise twice a week ; I exercise twice one week

他多久锻炼一次 How often he tempered ; How often does he exercise

一周锻炼三次 Exercise three times a week

她多久锻炼一次 Her long training time ; How long does it take her temper ; How long will she exercise

每月锻炼一次 Exercise once a month

我一次每周锻炼 i exercise once a week

你多久锻炼一次 How often do you exercise

我妈妈每周锻炼一次 My mother once weekly workout