八年级上册英语第二单元学习了一些单词，短语，句型以及how often对频率副词或者频率短语进行提问。具体包括，ever,hardly,once,twice,Internet,
program,percent,online,hardly ever
once a week, twice a week,
How often do you exercise?
Three times a week.
八年级上册英语第二单元，主要讲了你多久运动一次。一般现在时How often的用法及其回答。同时，也学习了How many,How much, How about, How long等的用法
