IV. Translate the following sentences . Pay attention to the modal verbs:

Heat is a form of energy and may be measured in the units which energy is measured.

We must say that the discovery of at energy is as important as the discovery of fire. 3. Electronic machines can add subtract, multiply and divide much quicker than man 4. The

origin of automation can be traced back to the early days of the industrial revolution. 5. She may use different methods in her research work. 6. For a long time scientists could not discover the secret of atom. 7. This equipment can work with high accuracy. 8 You may those devices in your research work. 9. The atom is a great force that must be used for the good of mankind. 10, Chemists must create the materials which don't exist in nature. 11. Naturally, this circuit can be modified if necessary. 12. This kind of energy must find application in transport.

V. Choose the sentences where the verbs to have and to be ore used in the functions of modal verbs and translate them:

1. These devices have been used in our experiment. 2. Scientists have to work hard to create a new atomic technique. 3. A modern computer has two main parts: a memory and a computing unit. 4. As the known resources of coat and oil are limited, man has to find new sources of power. 5, Very difficult calculations in mathematics and electrical engineering have to be solved by computers. 6. People of good will have to struggle for peaceful use of atomic energy. 7. When technique reached a very high stage of development, new methods of work will become possible, 8, We are to take into consideration all the advantages and disadvantages of this device for the future work. 9. We are to lake special steps to reduce the weight of this mechanical part. 10. These new data are obtained after our experiment. 11. At present our engineers are to develop the most advanced methods of production. 12. Our design bureau has to construct a new adding machine, 13. This device has been used in our experiment. 14. The experts are to inspect _this plant.

VI. Translate the sentences. Pay attention to the use of modal verbs and their equivalents:

1. Without a computer scientists will not be able to solve complicated problems. 2. Modern computers can multiply two numbers in a microsecond. 3. This machine can do the work of hundreds of workers. 3. He has to finish his experiment in time. 4. She was allowed to carry out this research as she had taken part in the scientific symposium. 5. Every student must know the difference between automation and mechanization. 6. With the help of radioactive elements we were able to measure the thickness of various materials. 7. Every engineer must improve his technical knowledge. 8. Scientists of different countries must cooperate in their research and peaceful application of their discoveries. 9. In fact, there is hardly any sphere of life where the atom may not find useful application. 10. The computer can perform different mathematical operations. 11. Our plant is to increase its output. 12. Every plant must fulfill its plan in time. 13. Workers must apply new methods of production.