As middle school students, being safe(安全) is important. How can we keep safe in a new place? Some rules can help you.

Before you go out, remember the three “W”s: Always tell your parents WHERE you are going, WHO you are going with and WHEN you will get back home.

Make sure you know where your home is and what your parent’s telephone number is.

Say “No” loudly if someone wants to make you feel unhappy.

Shout loudly and run away if someone wants to make you go with him/ her or wants to make you do the things you don’t like.

Some strangers look very friendly, but never talk to them and never take gifts from them. You mustn’t do like that.

If you get lost in a new place, be careful of whom you ask for help. Ask a policeman or someone with a child for help.

You may think it’s not easy to keep safe. But if you follow these rules, you’ll be safe.

The Garbage (垃圾) Project started at the University of Arizona in 1973. Since then, the students and teachers in it have studied the modern garbage in different cities.

To study the garbage, the students had to travel to landfills, the places where cities bury (填埋) their garbage. While the students were studying the garbage, they wore special clothes. Students were very careful when they opened bags of garbage.

One important thing the students have learned from studying the garbage is that the garbage in landfills disappears very slowly. That was surprising to both the students and many scientists who had thought that about 70% of the garbage in landfills would disappear quickly. Even in cities where it rains a lot, the students found newspapers from 1948, 40-year-old hot dogs, and vegetables from 1970. And the students also found many more empty bottles of cola than they expected.

As society develops, there is more and more waste produced in our daily life. How to dispose of our garbage well depends on what kind of garbage it is: regular (普通的) garbage, dangerous materials, or recyclable materials, such as newspapers and glass bottles. Regular garbage goes to regular landfills. Dangerous materials are harmful to people’s health and the environment. They shouldn’t go into regular landfills. And people should try their best to reuse the resource and reduce the amount of using them. It is high time that people need to divide different kinds of waste and put them into different dustbins, which will be a great help to cleaning workers as well as the whole society.

Homes are full of dangerous waste. One kind of the dangerous waste in homes is batteries (电池). When batteries are buried directly in a landfill, they often break open. The poison inside them moves through rain water to the bottom of the landfill. Then it can pollute the natural water in the ground.

Another dangerous waste from homes is motor oil. When people pour old motor oil on the ground or throw it in the garbage, it pollutes the environment.

Our garbage problem is not new, but as the world’s population continues to grow, it will become a bigger and bigger problem.

As we all know, water is the source of life. Nothing can take the place of it. But it has some trouble. So it’s necessary for us to save and protect water in our life.

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The Loess Plateau (黄土高原) soil loss is very serious because there are fewer and fewer trees and plants. Also the rain in summer is heavy so the soil is very easy to lose. What’s more, people dig up grass and cut down trees to grow crops and build roads. The soil loss makes it difficult to control the flood.

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There are many causes of water pollution. The main causes are industrial waste water, agricultural (农业的) waste water and life sewage (污水). Waste water can be produced in every step of industry and agriculture. Sewage can be produced by people in their daily life.

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Beijing, one of the world’s cities facing the greatest water shortage, aims to become a “sponge (海绵) city” to collect and use rainfall in the future. Wuhan started to build itself as a “sponge city”. It built many gardens, ponds and wetlands around the city. When it rains, they can take water like a sponge. Then the city has less flooding.

Do you know what the sponge city is like? It means cities can keep and clean water like the sponge. Every year many activities are held to encourage people to think up more ways to save water resources.

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