Write a new sentence with the same meaning
1. Somebody has stolen my keys. My keys have been stolen.
2. Somebody stole my car last week. My car…………….
3. Somebody wants you on the phone. You……………..
4. Somebody has eaten the bananas. The………………..
5. Somebody will repair the machine. The……………….
6. Somebody is watching us. We ………………………..
7. Somebody has to buy the food. The …………………..
Complete the sentences.
1. We were invited (invite) to the party but we didn’t go.
2. The museum is very popular. Every year it ………………. (visit) by thousands of people.
3. Many buildings …………. (damage) in the storm last week.
4. A new road is going to ……………. (build) next year.
5. “Where is your jacket?” “It …………… (clean). It will be ready tomorrow.”
6. She is famous now. But in a few years her name will ………………. (forget).
7. “Shall I do the washing up?” No, it ……………….. (already /do).
8. Milk should ……………… (keep) in a fridge.
9. ……………………… you/ ever /bite by a snake.
10. My bag ……………. (steal) from my car yesterday afternoon.
Unit 2 Traditional and Modern Building Materials
1. Read the text:
Modern Building Materials
Concrete is perhaps the most widely spread building material used nowadays. Concrete is an artificial stone, made by thoroughly mixing such natural ingredients or aggregates as cement, sand and gravel or broken stone together with sufficient water to produce a mixture of the proper consistency. It has many valuable properties. It sets under water, can be poured into moulds so as to get almost any desirable form, and together with steel in reinforced concrete it has very high strength, and also resist fire. Prestressed concrete is most widely used at present while prefabricated blocks are employed on vast scale for skeleton structures.
Aggregate for concrete
By the simple definition from the dictionary “aggregates are the materials, such as sand and small stones, that are mixed with cement to form concrete.
Aggregates have three principle functions in the concrete: they provide a relatively cheap filler for the concreting material, or binder, they provide a mass of particles which are suitable for resisting the action of applied loads, of abrasion, of percolation of moisture through the mass, and of climate factors, they reduce volume changes resulting from the action of the setting and hardening of the concrete mass.
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All aggregates, both natural and artificial, which nave sufficient strength and resistance to weathering, and which do not contain harmful impurities may be used for making concrete.
As aggregates such natural materials as sand, pebbles, broken stone, broken brick, gravel, slag, cinder, pumice and others can be used.
Prestressed concreteis not a new material. Its successful use has been developed rapidly during the last two decades, chiefly because steel of a more suitable character has been produced. Concrete is strong in compression but weak when used for tensile stresses.
If, therefore, we consider a beam made of plain concrete, and spanning a certain distance, it will at once be realized that the beam’s own weight will cause the beam to ‘sag’ or bend. This sagging at once puts the lower edge of the beam in tension, and if the cross-sectional are is small, causes it to break, especially if the span is relatively large. If, on the other hand, we use the similar cross-section, but incorporate steel bars in the lower portion, the steel will resist the tensile stress derived from the sagof the beam, and thus assist in preventing it from breaking.
Key vocabulary
Bend – v сгибаться; гнуться; изгибаться
Crack – n 1.треск 2.трещина
Desire- желание; просьба, требование
Gravel - гравий
Load – n груз; нагрузка
Sag – v оседать; падать
Store – n запас; склад
Tensile – растяжимый
- GRAMMAR FOCUS
Passive Voice
1. Complete the sentences in the text:
The National Trust
There are lots of beautiful, large houses in Britain. Many of them (1) …………… built hundreds of years ago. In the past, they (2) …………… owned by very rich families. Today, many of them (3) ……………owned by an organization called the National Trust, which (4) ………….. created to look after them. The houses (5) ……………. kept in perfect condition, and visitors (6) ………… allowed to look round them. It’s interesting to learn how different life was in an old house. Milk was (7) ……….. kept in the fridge, because they didn’t have fridges. Milk was (7) ……… kept in the fridge, because they didn’t have fridges! Washing machines (8) ……….. only invented very recently, so washing (9) ………… done by hand. In some cases, the house (10) ………… still lived in today. When this happens, visitors (11) ……….. only shown part of the house. The private rooms (12) ……. kept close to the public. These houses often have beautiful gardens, too. The gardens (13) ……….. looked after by professional gardeners. You usually have to pay to look round National Trust houses. Members of the National Trust (14) ……… given a discount. This year, millions of people (15) ……… be given the chance to see what life in an old country house was like.
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