题：
A computer can give a quick response and people don't need to use their imagination. While reading a book,people have to slowly let the story develop and picture , things and people in the story in their minds.

根据以上信息填空：

Computers show images , while _______ require you to understand the meaning of the text on your own.

请帮忙翻译以下，并说明为什么要那样填。
先谢谢了！

填books。
电脑可以给与快速的答复，使人们不必自己思考。但是阅读书籍，人们就不得不慢慢地思考，使故事的发展、画面、事件、人物显现在头脑中。

while表对比，a computer与a book是对比关系。
需要填空的句子里是复数，所以填books。