Christmas is one of the most important festivals in some Western countries.Now it is celebrated in many countries including China.The practice of putting up special decorations on Christmas has a long history.Long ago,people in Rome brought branches from evergreen plants indoors in the winter,Decorating with green plants is also part of Jewish tradition.

    When Christmas Day comes,we can see some traditional colors everywhere.The traditional colors of Christmas are green and red.White,silver and gold are also popular.Red stands for the blood of Jesus and green stands for eternal life.People like to decorate their houses with the evergreen tree because it does not lose its leaves in the winter.

    Decorating the Christmas tree is a tradition when Christmas Day comes.The phrase“Christmas tree”is first recorded in 1835.The modern Christmas tree tradition is believed to have begun in Germany in the 18th century though many people argued that Martin Luther began the tradition in the 16th century.

    Christmas lights and banners may be hung along streets,music played from speakers,and Christmas trees placed in prominent places.It is common in many parts of the world for town squares and shopping areas to display decorations.In some countries,Christmas decorations are traditionally taken down in the evening of January 5.

    Today there are policemen everywhere, but in 1700, London had no policemen at all. A few old men used to protect the city streets at night and they were not paid.

    About 300 years ago, London was starting to get bigger and more and more people began to live there. The city was very dirty and many people were poor. There were so many thieves who stole money in the streets that people stayed in their houses as much as possible.

    In 1749, Henry Fielding started to pay a group of people for stopping thieves. They were like policemen and were called "Bow Street Runners" because they worked near Bow Street.

    Fifty years later, there were about 120"Bow Street Runners", but London had become very big and needed more policemen. So in 1829, the first Metropolitan (or London) Police Service was started with about 3, 000 officers. Most of the men worked on foot, but a few rode horses.

Today, London police are quite well—paid and for the few police officers who still ride horses, the pay is even higher than for the others.

    Green is an important color in nature. It is the color of grass and the leaves on trees. It is also the color of most growing plants.

    Sometimes, the word "green" means young, fresh and growing. For example, a greenhorn is someone who has no experience. In the 15th century, a greenhorn was a young cow or an ox whose horns(角) had not yet developed. A century later, a greenhorn was a soldier who had no experience in war. By the 18th century, a greenhorn had the meaning it has today—a person who is new in a job.

    Someone who is good at growing plants is said to have a green thumb(大拇指). The expression comes from the early 20th century. A person with a green thumb can make plants grow quickly and well. The Green Revolution (绿色革命) is the name given some years ago to the development of new kinds of rice and other grains. It was the result of hard work by agricultural scientists who had green thumbs.

    Green is also the color used to describe the powerful feeling—jealousy(嫉妒). The green eyed monster is not a dangerous animal from outer space. It is an expression used about 400 years ago by the British writer William Shakespeare in his play Othello. It describes the unpleasant feeling when someone has something he wants.

    In most places in the world, a green light is a signal(信号) to move ahead. In everyday speech, a green light means approval(赞成) to continue with a project.