This sentence expresses three meanings.

First, reading can make people understand and learn knowledge.

Second, there is a lot of knowledge in the book. Only by reading more can you learn knowledge.

Third, there are good and bad books. Try reading books that are of great benefit to you.

Extended data:

Memory of Reading This is an article written by Bing Xin, an old man, about how to read. The content is simple and to the point, easy to understand. ? By recalling the author's reading experience when he was a child and young, as well as many years' reading experience, this paper encourages young people to "study hard, read more and study hard". ?

The benefits of reading:

The vivid story and characters in the book can arouse people's emotions and make people enjoy all kinds of beauty.

②? Reading can broaden your knowledge.

③? Reading is of great help to writing.

④? Reading helps to improve people's moral cultivation. ?