The people-----usually take exercise are heathy.填those还是who为什么?
问题描述：
The people-----usually take exercise are heathy.填those还是who为什么?
答
who,引导修饰people的定语从句.句中缺少引导词,those无作为引导词的用法.
如果句子中The people替换为Those,也成立.即：
Those who usually take exercise are heathy.