With the development of science and technology， great changes have taken place to human life．（1） Some of these changes are great ， while some are harmful ．So people have lots of arguments about whether science and technology are dangerous or not．
If they are used by bad people， they can bring many problems． Besides， as technology becomes more and more powerful day by day，（2） 许多人会越来越懒惰．Even students' study ability and creativity will be weakened．
However， just like the saying goes， every coin has two sides．（3） There is no doubt that science and technology have made contributions in many areas ．If they are used correctly， they will be good for us． Therefore， the key lies in the user． Responsibility and goodness should never be lost in our heart． Otherwise， the world would be full of danger even we turn back to the Stone Age．
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