It's colder today than it was yesterday.
问题描述：
It's colder today than it was yesterday.
请问这里为什么要加it was呢,去掉可以吗?
答
不能省去.当两个不同的时间里的人或去对比时,不能省去后面的动词.
例：I study much harder than I did last year.
我比去年学习努力多了.