4. Answer the following questions:

1. How was native asphalt obtained in ancient times?

2. Where were large sources of native asphalt found?

3. What was asphalt used for?

4. What does the amount of asphalt in a crude oil depend on?

5. How is the crude oil transported to the refineries?

6. What processes are used in the refining of asphalt?

7. What is done to form a stable waterproofed base course?

Language focus

5. Build derivatives from the words below and translate them:

To vary – adj.; to resist – n.; to stabilize – n.;

to continue – adj.; to crack – n.; to coat – n.;

to extract – n.; to refine – n.; to form – n.;

stable – n.; proper – adv.

6. Match the following words with their synonyms:

a) to contain, to obtain, amount, to remain, to bind, course, to separate, way, to apply, fraction, to aid.

b) quantity, to get, to involve, method, to connect, to divide, layer, to help, to stay, particle, to use.

7. Put the correct forms of the words into the sentences:

Nature works its wonders

Sir Waller Raleigh ___________ on the island of Trinidad in 1595 and stayed there long enough to obtain a ____________ ofasphalt. The asphalt he used was a native asphalt ________ from an asphalt lake a short distance from the shore of the Gulf of Paria and was similar to that __________ by the ancienls. Hundreds of thousands of tons of asphalt have been _______ from the Trinidad lake without any sign of loss. As the material removed, pressure deep in the earth ________ more of the heavy residue to the surface, where nature continues its ____________ process. The natural asphalt ________ from the lake ________ many impurities and foreign matter such as water, fine sand and vegetation. To produce a _____________ paving material, these impurities have to be _________; therefore a refining process is necessary.

to land to supply to take to use to remove to force to refine to remove to contain to suit to remove

8. Translate from Russian into English:

1. Асфальт является природным материалом, получаемым из нефтяных скважин.

2. Сырую нефть транспортируют на нефтеочистительные заводы, где её разделяют на различные составные элементы.

3. Количество асфальта в сырой нефти зависит от её плотности.

4. Чем выше плотность сырой нефти, тем выше содержание асфальта.

5. При очистке асфальта используется два метода: метод паровой и вакуумной дистилляции, а также метод экстракции селективным растворителем.

6.Укрепление грунта или заполнителя асфальтом широко используется при строительстве дорог и аэродромов.

7. Тонкое покрытие асфальтом вокруг частиц грунта обеспечивает высокую степень водонепроницаемости основания дорожной одежды.

9. Read the text and choose the right statement:

Some interesting facts

One of man's oldest building materials is finding its way into a lot of new places these days. Concrete, first discovered by the Romans, is now more widely used in construction than all other materials together.

The magic ingredient that makes concrete possible is cement, about which, according to one expert, more has been learnt in the past three decades than in the preceding 2,000 years. Concrete is a synthetic stone which can be formed while soft into practically any shape the builder wants. Portland cement mixed with water is the paste that binds sand, gravel, clinker (шлак) into an artificial rock that becomes harder as the years pass. Portland cement does not come from a place of that name; it was called Portland because Joseph Aspdin, the English builder who invented the first dependable, scientifically made cement about 1824, thought it resembled (напоминать) the rock excavated on the Isle of Portland on the Dorset Coast.

Portland cement is called …

1. after the name of the person invented it;

2. after the name of the place it had been formed;

3. after the name of the island where the mineral it is similar to was excavated.

UNIT IV. THE ROAD. GENERAL INFORMATION

Pre-reading tasks