7. Make the sentences interrogative:

1. I know how to spell this word.

2. She is only beginning to write the letter.

3. He seems to have translated the works of many American authors.

4. Our graduates want to work at many different enterprises of the town.

5. Our Institute prepares engineers for many branches of industry.

8. State the function of the Infinitive:

1. You study at the Institute to become qualified specialists.

2. The problem to be solved was of great importance.

3. To master English it is necessary to work hard.

4. We are very glad to have listened to the professor’s lecture.

5. The engineers had several problems to solve.

6. The students have a lot of work to do.

7. Do you know how to write the letters?

9. Define the form of the Infinitive. Comment on its syntactic function. Translate into Ukrainian.

1. To dissolve this substance is difficult.

2. The design of a mechanism depends on the work to be done.

3. The company advises to buy this equipment.

4. The scientist is sorry not to have found another solution to that problem.

5. As soon as the experiment was over the engineer began to record the results.

6. To understand many parts of electronics we must know how electricity behaves at higher frequencies.

10. Translate the following sentences into English:

1. Сталь – один з найстійкіших металів.

2. Легуючими елементами для виготовлення сталі є нікель, хром, марганець тощо.

3. Марганець підвищує зносостійкість сталі.

4. Пісок, який використовується для виготовлення форм для литва, повинен бути вогнестійким та крупнозернистим.

5. Нікель підвищує стійкість та міцність сталі.

6. Відливки із сталі використовуються тоді, коли потрібна велика міцність.

7. Для того, щоб виготовити сталь, залізо необхідно сполучити з вуглецем та легуючими елементами.

8. Інструментальна сталь може бути використана для виготовлення інструментів та робочих частин верстатів.

9. Вуглекислі сталі складаються з заліза та вуглецю.

10. Використовувати сталі відповідно до їх властивостей – проблема інженера.

Discussion

1. Are the following statements about the text true or false? Why?

1. Wrought iron, cast iron and steel are ferrous materials.

2. Carbon doesn’t make a good deal of difference in the kind of metal produced.

3. Steel has more carbon than cast iron, and usually less than wrought iron.

4. Machine steels are very soft and can be used to make machine parts that do not need strength.

5. Nickel makes steel rust-resistant and in this case it is called “stainless steel”.

6. Much research is being done to improve not only the strength of steel, but also its wearing qualities.

2. Answer the following questions.

1. What is steel?

2. What are the main types of steel depending on the carbon content?

3. What are the most common steels used in industry?

4. What properties of machine steels do you know?

5. What manufacturing purposes may tool steel be used for?

6. What is alloy steel?

7. What alloying elements are present in alloy steels?

8. What sand is used for making steel castings?

9. Where are cast steels used?

10. What does the tensile strength of steel depend on?