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Plastic
We use plastic wrap to protect our foods. We put our garbage in plastic bags or plastic cans. We sit on plastic chairs, play with plastic toys, drink from plastic cups, and wash our hair with shampoo from plastic bottles!
Plastic does not grow in nature. It is made by mixing certain things together. We call it a produced or manufactured material. Plastic was first made in the 1860s from plants, such as wood and cotton. That plastic was soft and burned easily.
The first modern plastics were made in the 1930s. Most clear plastic starts out as thick, black oil. That plastic coating inside a pan begins as natural gas.
Over the years, hundreds of different plastics have been developed. Some are hard and strong. Some are soft and bendable. Some are clear. Some are many-colored. There is a plastic for almost every need. Scientists continue to experiment with plastics. They hope to find even ways to use them!
The United Nations
In 1945, representatives of 50 nations met to plan this organization. It was called the United Nations. After the war, many more nations joined.
There are two major parts of the United Nations. One is called the General Assembly. In the General Assembly, every member nation is represented and has an equal vote.
The second part is called the Security Council. It has representatives of just 15 nations. Five nations are permanent members: the United States, Russia, France, Britain, and China. The 10 other members are elected every two years by the General Assembly.
The major job of the Security Council is to keep peace in the world. If necessary, it can send troops from member nations to try to stop little wars before they turn into big ones.
It is hard to get the nations of the Security Council to agree on when this is necessary. But they did vote to try to stop wars.
Useful Words and Expressions:
1. representative 代表
2. General Assembly 联合国大会
3. permanent 永久的，持久的
4. Security Council 联合国安全理事会