Copy and complete the table in your notebook. Then use the completed table to present the two rivers to the class.

Sample letter to a friend in english № 1dear michael,     thank you for your recent letter. it is so wonderful to hear from you!   i am very glad that you had a good vacation.     as for me, i also spent a wonderful vacation. first, i lived with my parents in the garden. the weather was hot and i  swam  a lot with my friends. we played soccer and rode bicycles.      and in august we went  to  cyprus   with my parents. it is a large island in the mediterranean with a wonderful climate. we swam in the sea and were lying in  the shade of huge eucalyptus trees. we traveled along the mountain paths and  played  tennis. anyway, it was a memorable summer.     how did your academic year begin?   are  there newcomers in your class? any new subjects?     i’m sorry, i have to go to the sports section.     all the best!     ivan sample letter to a friend in english № 2dear paul, thank you for your letter. i'm so glad to hear from you. it's great that you're on vacation in italy. you ask me how i spent the summer. i rested at a youth camp on the lake chebarkul is located in chelyabinsk region in russia. i can not say that the summer was very hot, but at the camp we had fun. we play games, play sports, go to the disco. as for me, i really liked the large and beautiful lake. moreover, i had a lot of new friends! and you have many friends? who's best friend? why are you friends with him? sorry, i must go. i look forward to hearing from you. best wishes, tanya sample letter to a friend in english № 3 dear paul, thank you for your letter. i'm happy to get it.in your letter you ask me how i spent my summer. i think that most people spend the summer on the shores of ponds, swimming and sunbathing. as for me, i spent the summer with his grandmother in the village. we walked a lot in the woods, picking berries and mushrooms. i've seen a lot of wild animals and birds. moreover, we met a large moose with huge antlers. i did not think that the forest is so interesting! how did you start out? there are new lessons? you learn in school last year? sorry, i have to go now.  write back soon!   best wishes, alex

Он написал множество математических трудов, однако математики заклеймили его "еретиком" - создателем первой не-эвклидовой геометрии. Геометрическая система Эвклида единолично правила в на протяжении двадцати столетий. Учёные повсеместно считали, что математика, а в особенности, геометрия, состояла из аксиом, существующих непосредственно от человека. Два плюс два всегда дают в сумме четыре, а сумма трёх углов треугольника обязана быть равна 180 градусам.
Лобачевский сделал рискованный шаг и создал новую геометрию,  не предназначенную для обозначения реальности. Это была лишь самодостаточная математическая система на поверхности так называемой псевдосферы. Геометрия Лобачевского стала революцией как в математике, так и в философии науки.