In general you've done what you said you were going to do in your intro, even though it was a lot of work and a very ambitious goal! I wondered how you were going to deal with three items in two paragraphs, but you managed it somehow, mainly by putting tv and movies together.

I would change your intro slightly to make it more specific to the essay topic:

However, with both merits and demerits, none of them are perfectly satisfactory. This essay attempts to analyze both sides of these three medias and finally presents my favorable one.

This essay attempts to analyze which medium communicates most effectively and states why I prefer television.

A couple of small vocab and usage points:

• none of them are is perfectly satisfactory  (words like 'everyone, someone, anyone, no-one, none, everybody, anybody, nobody') are all singular.e.g. "everybody likes icecream"
• books cover almost all fields of human beings ==> books cover almost all fields of human thought and activity, OR books cover almost all human thought and activity
• Finally, when read reading books, people can highlight the key points 
• televisions and movies are still favored by some people in terms of its their entertaining function (pronoun reference -  the television and movies means the word should be plural)
• you are more likely to get the latest information on televisions and movies than on in books

Overall a good job with some good examples and arguments. I hope you can help some other people here with your comments and suggestions!

There is no doubt that books hold a vaster variety of knowledge than televisions and movies. As a traditional means of information transferring, books cover almost all fields of human beings, ranging from ancient human history to modern technology. Televisions and movies, in contrast, due to high cost and limitation of making conditions, may focus only certain fields. For instance, not all classical reading materials can be made into television programs and movies. Besides, books are rereadable, while televisions and movies are quite time-constrained. Once you miss the information presented on television or movies, you may not get access to it again. Finally, when read books, people can highlight the key points and make down their comments in the margins, whereas TVs and movies are only available for watching and listening.

In spite of so many advantages of getting information through books, televisions and movies are still favored by some people in terms of its entertaining function. By saying this I mean screens do make information gaining more vivid and eye-catching. Furthermore, you are more likely to get the latest information on televisions and movies than on books. Usually, Books may need months to be published. Compared with televisions, movies are more costly and time-consuming.

As I see it, despite so many advantages of acquiring information through books and movies, I prefer to tend to watch TV because it can offer me the latest knowledge and information as well as afford me great entertainment.