1. I must / have to visit my friend. It is her birthday.
2. I can / must pay your rent. That’s the rule.
3. You mustn’t / can’t eat in the classroom. It’s forbidden.
4. Sally is ill. She has to /mustn’t stay in bed.
5. Can / Must I stay out late tonight?

We live in a polluted world, that is why more and more people are concerned about their health and that is why more and more of them start going in for sport.

Sport plays an important role in people's life. It is popular among the young and the old. Many people do morning exercises, go jogging and go to the gym. Others prefer watching sports games on TV and listening to sports news rather than going in for sport.

There are some reasons for that. The main reason is that sport takes a lot of time. If you want to be a professional sportsman, you will have to train hard several times a week, or even every day. Those who work hard making money can't afford that. But you can be an amateur, too. This means that you are not a professional sportsman and you go in for sport because you like it. A lot of people are sports amateurs today. In winter they ski and skate, they like playing football, cycling and roller-blading in summer.

Sport is also a good way to keep fit, and everybody knows that keeping fit and being healthy is important. A healthy person can work easily and live a happy life. Keeping fit has become an important part of our life. We should remember that we were not created for sitting at table all day, so it is very important to spend a few minutes doing some exercises every day.

Physical Education is an important subject in Russian schools now. Pupils have physical training twice a week. Boys and girls play volleyball and basketball during the lessons. School teachers turn pupils' training into enjoyment, not obligation. A lot of different competitions are held at school and many pupils take part in them. All participants try to get good results and win.

There are many kinds of sport in Russia. They are: football, hockey, skating and skiing. Russia is also known for its gymnasts, figure skaters and tennis players.

As for me, I do sport regularly. I am not a professional, I am an amateur. I play football with my friends and I jog in the morning. But my favourite sport is swimming and I go to the swimming-pool twice a week. This helps me feel fit and healthy. My father used to play football and hockey when he was a teenager but now he prefers watching these sports games on television. My mom likes watching figure skating.

But keeping fit doesn't mean only doing sport. It also includes the right way of eating. Nowadays it is very popular to go on a diet. On the one hand, it makes you feel better because you avoid eating fatty and unhealthy food, but on the other hand, some people start eating very little and they lose weight and do not look healthy at all.

You need to get all types of vitamins to keep your body healthy. You should eat fruit and vegetables because they contain a lot of important vitamins and one of them is vitamin C. Fruit and vegetables also have fiber, which is very important for our health.

A lot of people like spending most of their spare time watching TV or working at computers. Such people ruin their eyes and their muscles do not work well. This way of life is not healthy. There are also bad habits that can damage your health. They include smoking, drinking alcohol and taking drugs. A lot of young people prefer smoking to going in for sport and this is not good.

I try to lead a healthy life, because I like feeling fit and happy.

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