Задать к тексту 2 специальных и 1 общий вопрос: when i choose a material for a bike frame, i have to think about the properties of the material. how elastic ís it? if you bend or stretch it, will it go back to its original shape? if it does, it has high elasticity. how strong is it? there are two kinds of strength. the first is how much force you need to bend it to a point where it can't go back to its original shape. the second is the amount offorce you need to break it. steel is the least expensive choice. there's a wide range of standard gauge tubes available. it's strong and it has good elasticity but it's heavy. aluminium is líght and strong but it, s flexible. the more it bends, the quicker ít breaks. so aluminium bike frames use large diameter tubes. that limits the amount of bending. titanium has a great strength.to.weight ratío. it, s got good elasticity so when it bends it tends to return to its original shape. it's corrosion-resistant so you don, t need to paint it. but it's expensive - fifteen times the price of steel! the professíonals use carbon fibre. it's very light and it's very strong. you can shape it any way you like. but carbon-fibre frames are hand-made so they're very expensive

 What are two kinds of strength?

What limits the amount of bending?

Is steel the least expensive choice?

ну как-то

speed, excitement, danger. you can find all these in the different extreme sports that have become popular last 10 years. take bungee jumping. you jump off a bridge and you fall and fall, and then, just before you hit the ground or water, an elastic rope pulls you back. in skysurfing you jump out of aeroplane and use a board to “surf” the air, doing gymnastics in mid-air! and extreme sports on land can be just as dangerous.

winter sports have always an element of danger. for example snowboarding, which has all the excitement of surfing but on snow, is more dangerous even than skiing. probably the most dangerous of all the new winter sports is snowrafting. you sit in a rubber boat and sail down a mountain at great speed – and you can't control the boat!

of course, water sports have always been fun. ice diving, for those people who are absolutely crasy. you put on diving equipment and dive under a frosen lake. and, if that's not enough, you try to walk upside down on the ice! i feel cold just thinking about it.

a lot of people are not fit nowadays. it's a big problem today. if you want to feel fit you'd better go in for one kind of sport or another. i think that everyone must do all he can to be healthy. good health is better than the best medicine. all kinds of physical exercises are very useful to make our bodies strong and to keep ourselves fit and healthy. to tell the truth i don't do sports regularly and it is not an essential part of my daily life. in the morning i do some exercises just to awake. in summer i go swimming as there is a beautiful lake with pure water where my granny lives. in winter i swim in the swimming pool. i like to ride the bike. i shouldn't call myself a sports fan. of course , i like to watch sports competitions on tv, like hockey or football. but most of all i admire extreme kinds of sport. i think they are really cool.

1. young people tend to unite in groups or organisations because they enjoy being together.  2. wearing the same clothes or uniforms, listening to the same music and sharing the same ideas makes membership of such youth organisations or cultures more attractive, gives young people a sense of belonging. 3. young people are very impressionable and it is not so difficult for adults to use their enthusiasm to their own ends. history knows a lot of such examples.  4. young people should be very careful about their choice of organisations as it is a great responsibility.  5. political organisations for young people should not exist at all because children are not experienced enough to foresee the results of their activities.  6. there are very few youth organisations in ukraine at the moment and they are mostly adult-led political organisations.  7. youth cultures or cults usually annoy adults and they have a good reason for that.  8. some youth cultures can be dangerous for their participants.  b) give your point of view on youth organisations, movements or cults.