Ah, argumentative essays. A 100-word one is rather scam, more of an argumentative paragraph to be exact.
So for an argumentative essay, firstly you have to take a stand. Here I'll say that television is better than books. What you'll have to do is to come up with a thesis, then elaborate on it. Also anticipate counter-arguments, but break them down to support your thesis. 100 words is barely sufficient for one point actually, nevertheless it's worth a try.
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If you look at the wide range multimedia made available to us nowadays - books, printed media, television, internet - it seems almost impossible to decide which is the best for us. What I must say is that all have their own pros and cons, but here when I compare books and television, the feature of providing information is the most vital. The television, I believe, is better at providing us with information compared to books.
A closer insight will make you realise the effectiveness and efficiency of a television compared to a book. As it goes, a picture speaks a thousand words. When a documentary is played on television, how many pictures are flashed to you? And when you compare that to a 500-page book about the same topic, most would get the information much faster through pictures than text.
It is indeed true that with text, one is able to have a firm hold of the language features, and from there one can understand the content deeper and much better than with pictures flashing on a screen. However, if you compare with which you get the message and large picture faster and better, you would definitely say the television. Take the Legend of the Condor Heroes for example. A boring 4-book series with absolute text input to your brain can get you bored in half an hour (except for the bookworm enthusiasts of course). But when you turn to the 42-episode television series, you could have saved a whole lot of time, and whilst that understand the whole story much better. In the television series, however, you do miss some content in the book, but these pieces of content are normally unimportant, uninteresting, or simply have puny effects on the main picture of the story.
You can try it again, to choose between a book or television, to get the big picture, and to capture the whole content. If you want to save time and some brain cells, you will know what to choose.
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A little overshot though, with 336 words. You can trim it yourself. I don't really strive in essays in school (Well, 600 words for mine. How's that?), but this can bring you quite far.
Jiayou, you can do it!