同学你好，该知识点来自沪江网校《【Uni智能】英语零基础直达大学四级【全额奖学金班】》的课程，想要更系统的学习，欢迎进入课程学习。不仅可以和更多的同学一起学习，而且还有老师、助教随时的学习指导和知识点解答哦。

同学你好！
如果这句话说成：
People in those days liked to believe in computers that took over and ruled  the world.
那么就是把 that took over and ruled  the world. 看做了 computers 的宾语从句，
宾语从句中的that是连词，是不能充当句子成分的，只是起连接作用的，那么后面的这句话 took over and ruled  the world.就 没有主语了。
举个例子：
He told us that they would help us though the whole work.
如果同学这句话说成：People in those days liked to believe in computers that they took over and ruled  the world.