The American type of football was developed in the 19th century from soccer and rugby（橄榄球）football and it is one of the most popular sports in the world. The beginning of football may have been a game played by the ancient Greeks. In this game, there was no limit（限制）to the number of players.

    The football field of today is 120 yards long and about 53 yards wide. White lines are painted in the field to mark off the distance to the end area. The game is divided into four parts, each fifteen minutes long. The first two parts are known as the first half. There is a rest period （时间）between the two halves. It usually lasts about fifteen minutes.

    Each team has eleven players. Players are required to wear protective equipment（设备）to help keep the body safe during the game. Hard hats are worn to protect the head and the face. Pads（防护垫）are worn to protect the shoulders, arms and legs.

    The football is made of leather and is brown in colour. It is shaped much like an oval（椭圆形）and has white rings near each end of the football. These rings help the players see the ball when it is thrown or someone is running with it.

    The most famous football game of the year is the Super Bowl. It is televised around the world and is watched by millions of people each year.

    There are over 800 boarding (寄宿) schools in the UK with students from home and foreign countries. Boarding schools started hundreds of years ago in the country. But the earliest boarding schools were set up for white, rich boys only. Now both boys and girls can go to boarding schools from the age of 7 to 18.

    In the UK, boarding schools have three terms in a school year, with about 13 weeks in each term. Students study and live together. They can't go outside if they are not allowed to. In some schools, each student has his or her subject plan. Besides the usual classrooms and laboratories, the boarding schools have lots of other facilities for their students, including music rooms, boats, swimming pools, cinemas and theatres. Most boarding schools have a “light out” time. So when it's time to go to bed, all the lights in the bedrooms are turned off. There are house-masters to take care of students all the time, especially after school hours.

    Nearly all students at boarding schools wear a school uniform. Boys usually wear a shirt and a tie, and girls wear a white blouse, sometimes also a tie and a skirt. As students get older, the rules become less strict.

    In the UK, boarding schools provide students with delicious food. They can choose to have a full English breakfast or simply bread. For lunch and supper, they can choose a meal with or without meat. And there is always self-service for salad and dessert. Students can also make themselves something to eat at any time in a kitchen, or drink tea or have a snack between meals.