premise和assumption分辨

酸辣年糕

1avoid challenging the truth of the premises themselves. Focus on whether the argument is valid

2GMAT Question stems fall into a few broad categories:

ü Questions about Assumptions

ü Questions about Evidence

ü Questions about Structure

不是很清楚怎么分辨premise和assumption，求大牛指点

就比如下面这道作文题吧，应该怎么分析呢？

Studies have shown that students who go without lunch do poorly in school. Many students are hungry in school because they cannot afford to pack or buy lunch. Therefore, a program of free school lunches should help these students perform at grade level.