3. Equivalents of modal verbs

Ex. 1. Translate into Russian paying special attention to the equivalents of modal verbs. Ask a general question about every sentence:

1. In the near future such devices are to be used in Russia and in some other countries. 2. The development of these methods is to be the object of continuing work. 3. He was allowed to attend the seminar. 4. No doubt that this field of science is to provide challenges and opportunities for first class research. 5. Since many of the most important physical and chemical events take place on surfaces, extension of knowledge about them is to advance many fields of science. 6. These and other difficulties must be overcome if liquid crystal display devices are to perform all the diverse services of which they appear capable. 7. When a theoretical physicist attacks the problem of computing the properties of a solid, the basic ingredients he has to work with are a knowledge of the crystal structure of the sample and of the strength of the force between atoms. 8. They had to advance some explanation for these facts. 9. The scientists will have to take more than 1.2 million pictures during the experiment. 10. They are able to compare the results. 11. Scientists should develop this important branch of physics. 12. He should not change the speed of the operation. 13. Should the students have all the facts at their disposal? 14. He was allowed to attend the seminar. 15. Were they allowed to change the order of operations in the experiment? 16. They will not be allowed to work in the lab each Monday. 17. We shall be able to indicate the disadvantages of their method. 18. Will he be able to finish the work in time?

Ex. 2. Replace modal verbs with their equivalents:

1. He can not attend lectures now because he is ill. 2. I could not discuss it with my science adviser last Tuesday. 3. Might they check the work of the power station? 4. May he occupy the lab for today? 5. He might not take part in this investigation. 6. She must agree with both of them.

Ex . 3. Write down the following sentences in negative form:

1. They were to learn the third law of mechanics. 2. You will be able to obtain all the necessary books. 3. This new method has to be accepted as soon as possible. 4. He ought to read his paper at the seminar. 5. He was able to discover another fundamental law of nature. 6. It had to happen again. 7. We have to accept his words without proof. 8. He will have to give us all the details of the future experiment. 9. You are to discuss both of these properties. 10. The students were allowed to begin research.

4. The Present Perfect Tense

Ex. 1. Translate into Russian paying special attention to Present Perfect:

1. There have been two interesting meetings at our university this month. 2. According to the law of conservation of energy, the energy present in the Universe has always existed. 3. Many substances have been discovered spectroscopically in the Sun and in the stars. 4. Our present number system has not always been so fully developed as it is today. 5. They have made very important observations this month. 6. The great future of semiconductors has been generally recognized. 7. Who has brought these diagrams?

Ex. 2. Write down 1-6 sentences in interrogative form.

Ex. 3. Put the verbs in brackets in Present Perfect. Write down these sentences in negative form.

1. He (to pass) his examination in physics today. 2. We (to read) many books on the problem this year. 3. The equipment (to be brought) to the laboratory today. 4. We (to study) theses problems this week. 5. I (to look through) all the diagrams this week.