General understanding

Read the text attentively and answer the questions.

1. Why is timber one the most important raw materials?

2. What are artificial textiles manufactured from?

3. What is cellulose?

4. How are trees used in medicine?

5. Was timber used in prehistoric times?

6. What countries were the first to apply timber for construction purposes?

7. When was a scientific study of wood started?

8. What properties were studied first?

9. What was established and proved as a result of research work?

10. What was wood used for as a fibrous material?

11. Does timber grow in importance?

12. What products and materials are manufactured from wood nowadays?

Vocabulary

Exercise 1. Match the English words in A with their Russian equivalents in B.

A. B.

1. manufacture 1. применять

2. construction 2. доступный

3. apply 3. прочность

4. property 4. строительство

5. quality 5. рейки

6. strength 6. обрезки

7. available 7. отходы

8. edgings 8. доступный

9. trimmings 9. производить

10. residues 10. качество

Exercise 2. Find the English equivalents in the text to the following Russian.

ветка (отрасль); искусственный; волокно; цель; исследования; значительный; количество; данные; условие; рост; связь; источник; сосна; ель; опилки; сырье; древесностружечные плиты; древесноволокнистые плиты; использование.

Exercise 3. Choose the word from the text which has the similar meaning.

to produce; building; aim; to use; durability; amount; fir; to convert; wastes; broadly; use (n.); variety.

Exercise 4. Fill in the blanks with the words from the box.

1. Pulp is _______ used for making _______. 2. Woodworking _______ provide an excellent type of fuel. 3. ________ is a wood panel manufactured from small pieces of wood such as flakes, slabs, cuttings. 4. As timber is produced by nature _______ properties are highly variable. 5. Particle boards are very popular with _______ industry. 6. Different ________ of timber can be used to satisfy different uses and ________. 7. Wood is a natural resource that is widely ________ throughout the world. 8. Timber and wood products are generally safe in use and cause very little effect on the _______. 9. The _______ of timber are mainly determined by its structural composition.

Grammar

Exercise 1. Compare the sentences.

1. He asks – He is asked.

He asked – He was asked.

He will ask – He will be asked.

2. He told them an interesting story.

He was told an interesting story.

3. They will show a new film tomorrow.

They will be shown a new film tomorrow.

4. The engineer sent for the documents.

The engineer was sent for when the delegation arrived.

Exercise 2. Choose the correct verb form: active or passive.

1. Wood (forms; is formed) during spring and summer seasons. 2. Wood (composes; is composed) of carbon compounds. 3. Primitive people (used; were used) wood for tools and weapons. 4. As the tree grows sapwood (turns; is turned) into heartwood. 5. Some kinds of wood (attack; are attacked) by insects, especially beetles causing great damage. 6. Decay also (reduces; is reduced) the density of the wood. 7. Exterior woodwork (can protect; can be protected) against weathering by coating with paint. 8. The paint film on exterior woodwork (must renew; must be renewed) regularly. 9. The use of timber (depends; is depended) on its physical properties in the first place. 10. Decay (brings; is brought) about by the action of fungi and bacteria. 11. The sharp toothed metal saw (used; was used) in Britain before the coming of the Romans. 12. In Northern Europe logs (convert; are converted) into boards by frame saws.

Exercise 3. Choose the right voice (active, passive) and put the verb in the correct tense.

1. The traditional cottages in Russia (to build; to be built) of solid logs. 2. Many timber merchants of the past (to deal; to be dealt) in softwoods imported from the Baltic. 3. Particle boards (to produce; to be produced) from particles of wood such as chips or sawdust under pressure. 4. We (to use; to be used) walnut for decorative purposes. 5. Wood (to use; to be used) for the production of paper more than a century ago. 6. Great attention (to pay; to be paid) to conditions of the growth of the trees. 7. The first researchers (to pay; to be paid) great attention to the conditions of the growth of the tree. 8. The trunk of any tree (to cover; to be covered) by the bark. 9. The outer covering of the tree (to call; to be called) the bark.

Exercise 4. Translate from Russian into English.

1. Лесопильный завод реконструировали два года назад. 2. Процесс удаления влажности называют сушкой. 3. Древесину сушат в специальных Каме-

рах до требуемой влажности. 4. На скорость сушки пиломатериалов влияет способ штабелевки досок. 5. Древесину необходимо обрабатывать антисептиками. 6. На бирже (log yard) бревна должны быть окорены, рассортированы и отправлены в цех на распиловку. 7. На лес ссылались как на лучший

строительный материал греки и римляне.

Speaking

Speak about:

1. The wide use of timber in our life.

2. The use of timber in prehistoric times.

3. A scientific study of wood.

4. The use of wood residues.

Unit 4

Grammar:

Wood formation

Wood is a fascinating natural material to use, study and admire. From the very earliest times man has used wood for tools and weapons, buildings, furniture, or just as fuel for his fires. Nowadays wood serves very many purposes too. As a matter of fact, it is adaptable to both structural and decorative use.

But it is impossible to use valuable qualities of wood without gaining some knowledge of the structure and chemical composition of this material. Being a representative of the woody plants a tree has three main parts: roots, a stem and leaves.

A stem or a trunk has always been of the greatest value in the manufacture of wood products. The trunk has an outer covering called the bark which protects the wood from extremes of temperature, mechanical injury and harmful fungi and insects.

Between the bark and the wood there is a thin delicate tissue known as cambium. This tissue produces both the bark and the wood. The enlargement of the trunk in girth is brought about entirely by the activity of the cambium.

The production of wood and bark tissue occurs only when the cambium is growing. In temperate regions this occurs during the spring and summer months. During this period of time leaves in the tree's crown have to work hard. They are winning carbon dioxide from the air and transforming it into the new carbon

compounds the wood is composed of.

The roots are working hard as well. To supply the tree with mineral salts needed for its life processes the roots are carefully exploring the soil under the tree. All this time sap is actively flowing from the roots up the stem.

No wood is formed during autumn when the rhythm of growth slows down, nor in winter when the tree rests. Many trees are leafless at that time of the

year. New cells produced due to the activity of the cambium form layers of wood

called sapwood. The function of sapwood is to carry sap. A tree is getting older, slow chemical changes are taking place in its inner layers. As a result, sapwood is turned into heartwood.

Heartwood is harder and stronger than sapwood. In the majority of timbers heartwood is more resistant to decay. Therefore it is desirable to exclude the use of sapwood in situations where the likehood of fungi infection is considerable.

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