What do you regard as the most important modern invention?此题

What do you regard as the most important modern invention?此题目给个英文范文!
What do you regard as the most important modern invention?Describe this invention and give two or three reasons why it is important.
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这里下面有一篇,很长不过没采纳,你看看行不行.
下面是另一篇.不过字数不够.
The Greatest Invention In My Eyes
Good evening,ladies and gentlemen.Last night in my room,busy preparing for my speech today,I was puzzled at the opinions of greatest inventions of different persons.I read many books.Some articles hold the opinions that the greatest invention in the world is electricity,while the others believe computers are unreplaced in modern society.I read and read,suddenly an idea struke me:The greatest invention are just books.
A famous person has ever said:"Books are the best teachers."Exactly!That's what I would like to say first.In the long history of human being,books have playde an important part in communicating knowledge.And even today,the situation is still so .Each year,millions of books are published in the world.Knowledge changs our lives.If a knowledged person want to express some new idea,probably he wiil choose to write a book.On the other hand,the best way to broaden our horizens is reading books.
Secondly,as I have been puzzled,books provedes you with different ideas.And you make your decision to choose anyone that fit you.Or otherwise,you may choose none of them,just like me ,instead of obeying books' advise.I choose "books" as the greatest invention in my eyes.So,don't you think it's a little interesting?Books are honored as teachers without sound.But how are books different from our real teachers?I think the fact is that,if a real teacher advises me to choose electricity or computer as my topic today,and every one you can imagine,how much brave I will prepare to refuse.So don't you think books are better tempered and better get alongde than our real teachers?That's all,thank you.