do so 是什么用法?The tough people who survive the tough times do
do so 是什么用法?
The tough people who survive the tough times do so because they've chosen to react positively to their predicament.
xie xie 小猪
(who survive the tough times) 括号中的是一个定语从句,无法在后面句子中充当成分,而DO SO就是为了在避免重复的同时使该句可以在后面充当主语