阅读理解

     Most of you know this mathematical game, of course. You and your friend draw crosses and circles on a sheet of paper. You do it one after another. The first pupil who gets three marks in a row wins. But do you know that you can play this game another way and it will become more interesting? You must try to make your friend win. If you get your three marks in a row, you don't win — you lose!

     It is more difficult to play this game the other way. The second pupil can always win (if he plays the right way), but he may not win if the first pupil begins with his mark in the center. Then if the first pupil always takes a place on the other side of his friend's mark, nobody will win.
     If your friend does not know the secret which we have explained, you must play each time so as to leave him the greatest number of ways to win. You may try a few games and you will see how interesting it is to play the game this way.

    Soon computers and other machines will be able to remember you by looking at your eyes! The programme works because everyone's eyes are different. So in the future you won't have to remember a number when you want to use a machine or take money out of a bank. You'll just have to look at the machine and it will be able to tell who you are.
    The eye-recognition（识别）programme is already being tested in shops and banks in the USA, Britain, Spain, Italy and Turkey. Soon, this technology will take the place of all other ways of finding out who people are.
    However, scientists are working on other systems. Machines will soon be able to know you from the shape of your face or hand or even your smell! We already have machines that can tell who you are from your voice or the mark made by your finger.
    Eye-recognition is better than other kinds because your eyes don't change as you get older, or get dirty like hands or fingers. And even twins have different eyes, so the programme can be up to 94％ correct, depending on how good the technology is. Some programmes may only be right  51％ of the time. In Britain, it was found that 91％ of people who had tried it said that they liked the idea of eye-recognition. In the future your computer will be looking at you in the eye. So smile!

    We are lucky to live in a rich country where we have many things. However, most of us usually1 some things.

    Electricity(电) is one thing that we waste 2. Lights, TVs, 3 and other things are often kept on even when no one is using them. We should turn them off when we do not need them. It 4 less than a second to do it. Anyway, not wasting electricity saves money, because we do not have to 5 the electricity we do not use.

    The second thing that we often waste is water. Fresh water is precious(宝贵的) ， 6it shouldn't be wasted. It is only a simple matter of turning off a tap. I am sure 7 can do this easily if he wants to.

    8 big waste is food. My mother 9cook so much food that much of it was thrown away. I told her we had wasted so 10 food. She thought I was right and now cooks 11 what we can eat.

    It is not 12   to waste anything. I find there is a simple 13of not wasting things. That is to use only what we 14. Do not touch what we do not need. 15 this way we can stop being wasteful.

    The years from A.D 500 to 1450 are called the Middle ages. Sometimes they are also called the Dark Ages since few people had an education during that time. Still, there were lots of new ideas and inventions. Many of them came from China.