2. 1. Translate the sentences

1. Having discussed chemical reactions we proceeded to the experiments. 2. The experiment being made at our laboratory shows the action of catalysts. 3. Having been tested the computer system was installed at the plant. 4. A person beginning the experiment should be careful. 5. When studying metals Mendeleyev divided them into nine groups. 6. When compressing a gas heat may be developed. 7. Having been heated the substance changed its properties.

B. 2. Translate the sentences paying attention to the conjunctions

1. Computers are machines that are capable of very rapid and accurate calculations. 2. The man whom you saw at my house had made an interesting tour of the country. 3. I often visit the town where I lived in my childhood. 4. While you are having dinner I’ll be reading the newspaper. 5. He was reading a book when I came. 6. I shall go home after I have done my work. 7. Before he finishes the article the newspaper will be published. 8. As soon as autumn comes the birds will fly away. 9. As long as you apply old methods, you will not be able to accomplish this research. 10. I don’t know whether the test has begun. 11. They wanted to discuss what they had read in the newspaper.

B. 3. Translate the sentences

1. The subjects the students study in the first and second years are very important for their future speciality. 2. A number of electrons the atom loses or receives is called its valence. 3. The invention Popov made didn't interest the government. 4. The kind of house they built depended upon the climate. 5. Tungsten is valuable because of the several important properties it possesses. 6. It is difficult to imagine the world we live in without computers. 7. The particles all different atoms consist of are neutrons, protons and electrons. 8. The problem this article deals with is connected with the subject we study. 9. Even at the lowest temperatures we can obtain the common gases do not liquify and freeze if they are kept at low pressure.

B. 4. Translate the sentences

1. We were able to translate this text. 2. The old machines are to be replaced. 3. This angle can be measured. 4. One must observe certain experimental conditions. 5. He didn't have to make calculations. 6. One should know that "röntgen" is a unit of radiation 7. You can't do without air. 8. The solution (раствор) is to be purified. 9. They were allowed to continue the research. 10. Some materials with useful properties may be produced in space. 11. The development of new materials doesn't mean that old materials should lose their significance.

C. 1. Read the text THE DEVELOPMENT OF A HOUSE and answer the questions:

1. What were the most ancient houses in Rus?

2. What new elements were introduced by Greeks and Romans?

3. What are the advantages of precast concrete technique?

Most of the time of a modern man is spent within the walls of some buildings. Houses are built for dwelling; large buildings are constructed for individual purposes; theatres, museums, public and scientific institutions are built for cultural activities of the people. The purposes of modern buildings differ widely, but all of them originate from the efforts of primitive men to protect themselves from stormy weather, wild animals and human enemies.

The people of the Old Stone Age had to find some warm and dry place to shelter from bad weather. They chose caves, dwelling places that storm and cold could not destroy. Later caves were imitated in stone structures, trees were taken as a model for huts built of branches. Primitive stone structures, huts and tents are the earliest types of human dwellings.

Man has always been a builder. The kind of house he built depended upon the climate and upon the building materials at hand. The most ancient homes on the territory of Rus were earthen houses. They consisted of a shallow hole of oval shape. The floor was covered with limestone slabs. The roof was conical and stood on poles¹ covered by branches or animal skins.

The first houses in many parts of the world were made of wood. Men tied together the tops of several trees and covered them with the skins of animals or with leaves and grass. A hut was the first house of primitive people. In other regions the most convenient building material was stone. Men began building houses out of stone long ago.

The first kind of house in Britain was a simple one-room building of stone or wood, according to the materials the people could obtain. They were used about four thousand years ago. The people who lived in them were greatly in advance of the primitive men who used rock shelters. The walls of such houses were very thick, and the roof was made of whalebone rafters covered with skins, with a hole in the middle as a chimney. Those houses were plastered. A plastered house is warmer and looks nicer. There were no windows in such houses and the light came in through the hole in the roof. When it rained they covered the hole and opened the door.

The ancient houses of which anything is known are those of ancient Egypt. The Egyptians built very simple houses by present standards. They were built of bricks dried in the sun. Having dried the bricks², they put up four walls, and above these they placed a flat roof. The roof was flat because there was very little rain in Egypt. Some of them were built around a courtyard or garden with rooms opening into it. Their buildings were simple in construction but very beautiful. We still admire their monuments, pyramids, sphinxes and palaces. An important part in the history of building has been played by the column and ancient Egypt gave the world the lessons in the art of making columns. The Greeks learned much from Egypt. But they built a slanting roof because there was much rain in their country. They also improved on Egypt's column and soon became the teachers of the world in column making. In Rome bricks were used for building and houses were often finished with plaster over bricks on both inside and outside walls. The Romans, in turn, learned much from the Greeks. But they added the arch, thus adding much strength and beauty to their buildings.

A very advanced construction technique³ today is the use of precast concrete. It has many advantages over other building materials. Precast building units can be assembled at the site, the main part of the work is done at the factory. The precast concrete technique plays a great role in building.

Notes: whalebone китовый ус 1. стояла на столбах

2. высушив кирпичи 3. передовая технология строительства