I. Перепишите и письменно переведите предложения. Определите видовременную форму и залог сказуемого.

1. When the work had been completed the results were published in the

  magazine.

2. When the experiment was being made everybody was watching it with great

  interest.

3. A great deal of research work was done at this institute.

II. Перепишите и письменно переведите предложения, обращая внимание на разные значения слов it, that, one.

1. It was noisy in the hall as the students were talking about their summer

  holidays.

2. Last year the number of tourists to the Caucasus exceeded that of the previous

  one.

3. One must know traffic rules if one wants a drive a car safely.

III. Перепишите и письменно переведите предложения, обращая внимание на разные значения глаголов to be, to have, to do.

1. I have to translate the text but I have no dictionary.

2. The students usually do nothing on the day after the exam.

3. The weather was fine when we had our holidays.

4. He was only 12 when his family moved to Moscow.

5. Professor N was to deliver a lecture on history at the club.

IV. Перепишите и письменно переведите предложения, обращая внимание на функцию причастия, герундия, инфинитива.

1. Before writing our test we learn the necessary grammar rules.

2. Speaking about his new invention the young engineer told us many interesting

  things.

3. Alexei Leonov was the first man to step into space.

4. To build new electric stations is to develop our industry.

V. Прочтите и устно переведите текст. Перепишите и письменно переведите 1, 2, 3 и 4-й абзацы.

                            ENERGY AND ELECTRONS

1. The structure of atom is similar to planetary system, electrons orbiting around a certain nucleus. Electrons also rotate about their own axes. We know the rate of electron rotation and the orbital path determine the amount of energy passed by the atom.

2. The total energy contained in any atom is known to be the sum of the energies of the individual electrons. Electrons of a given atom can be changed from their position by different energies. Radioactive materials, for example, are constantly undergoing a change. Radioactive energy emitted from the material changes it from one form to another. It is also possible to change the atom structure by means of controlled nuclear reaction.

3. There is a simple method of changing the amount of energy in a given atomic structure. A photoelectric cell has a large area photocathode made from chemically active materials. These materials are alkali metals.

4. There are two basic laws of photo electricity. The first law states that the number of electrons released per unit of time from photoelectric surface is directly proportional to the intensity of the incident light ( падающий свет ).

5. The second law states that the maximum energy of electrons coming from photoelectric surface is independent of the intensity of the incident light and is directly proportional to the frequency of the light. The higher the frequency of incident of radiation, the higher is the energy of photoelectrons.

                        КОНТРОЛЬНОЕ ЗАДАНИЕ №3.

                                         ВАРИАНТ 2.

I. Перепишите и письменно переведите предложения. Определите видовременную форму и залог сказуемого.

1. After the lecture had been delivered we asked many questions, and the lecturer

  answered them.

2. Many specialists are trained for the national economy.

3. These students will be sent to Moscow to take part in the conference.

II. Перепишите и письменно переведите предложения, обращая внимание на разные значения слов it, that, one.

1. The crowd came close to the speaker, as it was interested in the theme of his

  speech.

2. One must choose a profession which one likes.

3. My room is very light, that of my brother is not so light but it is large.

III. Перепишите и письменно переведите предложения, обращая внимание на разные значения глаголов to be, to have, to do.

1. The examination paper had to contain not less than ten grammar exercises.

2. This book does not give any information on the history of chemistry.

3. I have been to Kiev this summer.

4. All the students were present at the lecture yesterday.

5. A new pump station is to be set up in this cotton-growing area.

IV. Перепишите и письменно переведите предложения, обращая внимание на функцию причастия, герундия, инфинитива.

1. He was informed about their coming to Moscow.

2. Energy is defined as the ability to do work.

3. While building the bridge the workers used new materials.

4. To study geometry means to train logical thinking.

V. Прочтите и устно переведите текст. Перепишите и письменно переведите 1, 2, 3 и 4-й абзацы.

                                 ATOM AND ELECTRON

1. Present atomic theories, based on the atom model, place the mass and the positive charge of an atom in a central nucleus, surrounded by moving electrons. The nucleus is composed of neutrons and protons. Neutrons have a mass approximately one-sixteenth that of the mass of the oxygen atom and have zero electrical charge. The proton has a mass slightly lighter than that of the neutron and approximately equal to the mass of the hydrogen H.

2. The chemical elements are differentiated by varying numbers of protons and neutrons in the nucleus, numbers of protons being equal to the atomic number, hydrogen having one, helium two, and so on.

3. The electron is the smallest known indivisible unit of electric charge. Early experimenters succeeded in the measuring the ratio of the charge of the electron to mass, and in 1910 the charge was first measured, thus determining these properties of the electron.

4. The electron appears to have a dual personality, at times being best thought of as a particle, and in other experiments seeming to require wave properties for a satisfactory explanation of the phenomena.

5. Electric current is due to the movement of electric charges, frequently referred to as electrons. However, long before the existence of the electron was known, it was customary to speak of electric current as due to movement of positive charges from positive to negative in a metallic circuit external to the source.

                          КОНТРОЛЬНОЕ ЗАДАНИЕ №3.

                                          ВАРИАНТ 3. 

I. Перепишите и письменно переведите предложения. Определите видовременную форму и залог сказуемого.

1. The construction of the oil center began after the plan had been adopted.

2. These text-books in chemistry were printed in our print shop.

3. A chain of thermal and atomic plants was built in 1970s in our country.

II. Перепишите и письменно переведите предложения, обращая внимание на разные значения слов it, that, one.

1. A barometer is an instrument that measures air pressure.

2. As the experiment was very interesting many people watched it.

3. One can easily forget foreign words that one does not use every day.

III. Перепишите и письменно переведите предложения, обращая внимание на разные значения глаголов to be, to have, to do.

1. Every candidate to the Institute has to take exams.

2. We did not know any student in that group.

3. He was the best football player of our school.

4. This new school building was to be ready last month.

5. Usually we have two lectures every day.

IV. Перепишите и письменно переведите предложения, обращая внимание на функцию причастия, герундия, инфинитива.

1. The teacher told the pupils to learn the poem by heart.

2. Seeing is believing.

3. The melting snow flows down from the roofs through pipes.

4. The transmitter operating on the low frequencies was constructed by these

  students.