1) During this period the track structure has been substantially improved. One of the greatest improvements was the elimination of rail joints. In order to reduce the number of joints the rails are welded into continuous lengths.These continuous or long welded rails have greater strength and provide a smoother running of trains at far greater speeds. 2) Another improvement which has made it possible to increase speeds on railways is the use of concrete sleepers. Thus in some countries , concrete sleepers have replaced wooden ones on heavily used main lines because of their advantages. Concrete sleepers have a longer life and a far greater weight than those made of wood. The greater weight of concrete sleepers provides the greater stability of track. It is this factor which has greatly contributed to increased speeds.
ответ взял прямо из текста. Насколько я помню, так надо делать в подобных заданиях.
1. Father (was watching) TV at ten o'clock yesterday. 2. I (went) to bed at nine o'clock yesterday. 3. I (finished) my homework at nine o'clock yesterday. 4. I (was playing) the piano at five o'clock yesterday. 5. He (began) to do his homework at four o'clock yesterday. 6. She (was washing) the floor at four o'clock yesterday. 7. I (met) Nick at three o'clock yesterday. 8. When I (came) home, Kate (was playing) the piano. 9. When I (met) John, he (was going) to the railway station. 10. When I (was going) to the museum, I (saw) a big crowd of people in the street. 11. They (played) in the yard in the evening yesterday. 12. They (were playing) in the yard the whole evening yesterday. 13. I (cleaned/was cleaning) my teeth at eight o'clock in the morning yesterday. 14. We (went) to the wood in summer. 15. When the teacher (opened) the door of the classroom, the pupils (were sitting) at their desks.
2) Another improvement which has made it possible to increase speeds on railways is the use of concrete sleepers. Thus in some countries , concrete sleepers have replaced wooden ones on heavily used main lines because of their advantages.
Concrete sleepers have a longer life and a far greater weight than those made of wood. The greater weight of concrete sleepers provides the greater stability of track.
It is this factor which has greatly contributed to increased speeds.
ответ взял прямо из текста. Насколько я помню, так надо делать в подобных заданиях.
2. I (went) to bed at nine o'clock yesterday.
3. I (finished) my homework at nine o'clock yesterday.
4. I (was playing) the piano at five o'clock yesterday.
5. He (began) to do his homework at four o'clock yesterday.
6. She (was washing) the floor at four o'clock yesterday.
7. I (met) Nick at three o'clock yesterday.
8. When I (came) home, Kate (was playing) the piano.
9. When I (met) John, he (was going) to the railway station.
10. When I (was going) to the museum, I (saw) a big crowd of people in the street.
11. They (played) in the yard in the evening yesterday.
12. They (were playing) in the yard the whole evening yesterday.
13. I (cleaned/was cleaning) my teeth at eight o'clock in the morning yesterday.
14. We (went) to the wood in summer.
15. When the teacher (opened) the door of the classroom, the pupils (were sitting) at their desks.