N.I. LOBACHEVSKY (1792-1856)

N.I. Lobachevsky is a great Russian mathematician and the creator of non-Euclidean geometry.1 He was born on December 1, 1792 inNizhni Novgorod in a poor family. When N. Lobachevsky was a child, his father died and the family moved to Kazan. There the boy learned at the "gymnasium" from 1802 to 1807 and in 1807 he entered KazanUniversity. At the University N.I. Lobachevsky spent the next forty years of his life as a student, professor and rector.
Lobachevsky became interested in2mathematics when he was still a schoolboy and he remained true to this science all his life long.
Lobachevsky did a lot to make KazanUniversity a first-rate4 educational institution of that time. At the same time he made extensive researches into mathematics.
On February 23, 1826 a great event took place at KazanUniversity. N.I. Lobachevsky presented a paper "A Brief Outline of the Principles of Geometry Strictly Demonstrating the Theorem of Parallel Lines." 5That day a new geometrical system, the so-called non-Euclidean geometry was born. In the paper he attacked the theory which was the basis of geometry for 2,000 years and made a real revolution in mathematics.
In the years that followed Lobachevsky wrote a number of6 works in the field of algebra and mathematical analysis. However, nearly nobody understood and recognized his works at that time. They were recognized only twelve years after his death.
Lobachevsky's ideas greatly influenced the development not only of geometry and other mathematical sciences, but also mechanics, physics and astronomy. One British mathematician called Lobachevsky "Copernicus of Geometry".

Notes
1. non-Euclidean geometry—неэвклидовагеометрия. Эвклид — (4—5 ВВ. Н.Э.)
древнегреческий философ
2. to become interested in — (за)интересоваться
3. to remain true to — оставатьсяверным(чему-л.)
4. first-rate — первоклассный
5. "A Brief Outline of the Principles of Geometry Strictly Demonstrating the Theorem of Parallel Lines" — «»
6. a number of— несколько

1. When I arrived at his house he was still sleeping.

2. A few months ago they began to build a new block a new of flats in this street.

3. They had been walking in the park for an hour when it began to rain.

4. When the door-bell rang, he stood up and went to the door,

5. The fire was still burning  at 6 o'clock this morning

6. Last summer I visited Riga. I enjoyed my trip very much

7. She cut her finger while she was cutting the bread and butter

8. He had come home by 6 o'clock yesterday.

9. When did she speak to him?- She spoke to him last week

10.The car had already gone when I looked into the street

11. I met him when he was crossing the street.

12. Last term Ann made good progress in her English

13. Wen I got out, the sun was shining.

14. Ann bought herself a new dress yesterday. She paid 3 pounds for it.

15. The had eaten everything by the time I arrived at the party.

16. Mary had worked in the shop 5 years before she became a manager

17.Our grandmother was cooking dinner from twelve till two yesterday

18. They had been walking in the park for an hour when it began to rain.

19. This time yesterday I was lying on the beach

20. They will reach the river by sunset.

21. Ken had been smoked for 30 years when he finally gave it up

22. I saw Carol at the party. She wore a really beautiful dress

23. He lived in Spain when he was a child

24. She couldn't find the book I had lent her

25. I saw Jim in the park. He was sitting on the grass and reading a book.

Объяснение:

1. When I arrived at his house he was still sleeping.

2. A few months ago they began to build a new block a new of flats in this street.

3. They had been walking in the park for an hour when it began to rain.

4. When the door-bell rang, he stood up and went to the door,

5. The fire was still burning  at 6 o'clock this morning

6. Last summer I visited Riga. I enjoyed my trip very much

7. She cut her finger while she was cutting the bread and butter

8. He had come home by 6 o'clock yesterday.

9. When did she speak to him?- She spoke to him last week

10.The car had already gone when I looked into the street

11. I met him when he was crossing the street.

12. Last term Ann made good progress in her English

13. Wen I got out, the sun was shining.

14. Ann bought herself a new dress yesterday. She paid 3 pounds for it.

15. The had eaten everything by the time I arrived at the party.

16. Mary had worked in the shop 5 years before she became a manager

17.Our grandmother was cooking dinner from twelve till two yesterday

18. They had been walking in the park for an hour when it began to rain.

19. This time yesterday I was lying on the beach

20. They will reach the river by sunset.

21. Ken had been smoked for 30 years when he finally gave it up

22. I saw Carol at the party. She wore a really beautiful dress

23. He lived in Spain when he was a child

24. She couldn't find the book I had lent her

25. I saw Jim in the park. He was sitting on the grass and reading a book.

Объяснение: