As we all know, there are three stages in study--preview, study in class and review, among which review is the most important. From my experience,I'd like to talk about the importance and steps of review. Firstly, make a review plan with certain contents of subjects at a certain time. Second]y, carry on the review plan regularly. Thirdly, examine what has been reviewed and make supplement in time. One thing to remember is to keep notes all the time. I follow my review plan strictly and have made progress in my study. It turns out to be good enough. Of course, there is more than one way to review. So long as we review regularly we can find more ways to improve our studies.
As we all know, the computer is a marvelous machine. It has all kinds of types. Nowadays most computers have a memory processor in which information can be stored and be taken out at any time.
The oldest kind of computer is the abacus. It was used in China long agoi The first modern computer was very large and expensive, but now scientists already have been making computers smaller and cheaper, at the same time easier to use and work faster and faster now.
Computers can be used a great deal in many ways. It can do many kinds of work. They can be used in doing business and science research work, in some large factories, and our daily life. We even use it to play computer games at home. Today a lot of people buy computers. Computers is becoming more and more popular indeed.
Water is very important for living things. Without water there can be no life on earth. All animals and plants need water. Man also needs water.
Water is found atmosteverywhere. Even in the driest part of the world there is some water in the air.
As we all have found out, water may be a solid, or a liquid or a gas.When it isa solid, it may be as hard as brick, When itis a liquid, you can pour it out of a container. When it is a gas, you cannot see or feel it.
Although about 70 percent of the earth's surface is covered with water,there are many places in the world still running out of water. So we should make good use of water on earth.
As we all know, plants and animals need water. So do the people's life and production, t,ife couldn't go on without water.
With the rapid development of agriculture and industry, more and more water is needed. Therefore, water is becoming scarce in many places. What's more, a lot of rivers and lakes are beginning polluted by the waste watcr from factories. Fish can't live in them any longer. At the same time, thc waste water does great harm to people's health.
In order to make rivers and lakes clean and prevent water from being polluted,we must do something to stop all sorts of pollution.