which is the most useful great inventions?what do you think?

The computer is a useful machine. It is one of the most important inventions. The oldest kind of computer is the abacus, used in China many centuries ago, but the first large and modern computer was invented in 1946. The computer could work out maths problems quite fast.
Now the computers are getting smaller and smaller, and computing faster and faster. Many scientists agree that computers can now do many things, but they cannot do everything. Who knows what the computers tomorrow will be like? Will computers bring good things or bad things to people? The scientists today have to decide how to use the computers tomorrow.
翻译：
电脑是一种有用的机器,它是最重要的发明之一,最古老的电脑是算盘,用于几世纪前的中国,但是最大和最现代化的电脑发明于1946年,电脑能很快的算出数学题目.
现在电脑变的越来越小,而且运行得越来越快,许多科学家同意现在的电脑可以做很多事,但它们不能做全部的事.谁知道以后的电脑会变成什么样?电脑会给人类带来好处还是坏处.如今的科学家不得不决定如何使用以后的电脑.
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