In my opinion,life in the twenty-first century is much easier than ________.

题目

In my opinion,life in the twenty-first century is much easier than ________.
A.that used to be B.it is used to C.it was used to D.it used to be
为什么不选A,that不也可指代么?我学比较级的时候用来代指天气等不可数名次都用that啊 怎么这个不是呢》?

答案

因为这里有“life”.这个词很特别,要用it指代.例：life is not as it used to be hard traffic ,hight prices ,people always become angry all the time ,we need to go to live on the moon