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  1. Read the text again and answer the questions that follow (1-7):

  1. Why is timber considered to retain its prime importance within the construction industry?

  2. What climate areas do hardwoods and softwoods cover?

  3. Which are natural polymers? Characterize each of them.

  4. What is commercially available among hardwoods?

  5. What kinds of trees are mentioned in the text?

  6. How can you characterize softwoods?

  7. What softwoods are preferable for external timber cladding? Why?

Follow-up

6 A) Find the synonyms for the words given in italics.

b) Explain the words in bold from the text and make up sentences of your own. Use English-English dictionaries to help you.

7 Give the English equivalents to the following and use 5 of them in small situations:

Строительная промышленность, покрыто лесами, приблизительно 2/3, ежегодные лесозаготовки,природный полимер, составлять около45%, согласно чему-либо, широколиственный, срок службы, покрытие из древесины твердых пород, наросты, преимущественно, возобновляемые ресурсы.

8 A) Scan the text, but at ten points fragments have been removed. Study the list with the missing fragments and decide where they go:

Timber, as a natural product, is rarely free from blemishes or defects. Timber imperfections 1) _____: natural, conversion and seasoning defects, according to whether they were present in the living tree, or arose during subsequent processing. Additionally, timber may be subjected to deterioration by weathering, fungal and insect attack and fire.

On prolonged exposure to sunlight, wind and rain, 2) _____ their natural colours and turn grey. Sunlight and oxygen break down some of the cellulose and lignin into water-soluble materials which are then leached out of the surface leaving it grey and denatured. Moisture movements, 3) _____, raise the surface grain, open up surface checks and cracks and increase the risk of subsequent fungal decay. Provided the weathering is superficial, the original appearance of the timber can be recovered by removing the denatured surface.

Wood preservatives contain pesticides in the form of insecticides and fungicides. Their use is therefore strictly controlled 4) _____ environmental damage.

Timber is an organic material and therefore combustible. Surface treatments, 5) _____, include antimony trioxide flame-retardant paints which are suitable for both interior and exterior use. Intumescent coatings, which swell up and char in fire, are suitable for most environments if overcoating is applied. However, 6) _____ may be negated by unsuitable covering or removal by redecoration.

  1. associated with repeated wetting and drying cycles;

  2. to limit unnecessary or accidental;

  3. which cause the evolution of non-combustible gases in fire;

  4. the protection afforded by surface treatments;

  5. can be divided into three main categories;

  6. external timbers gradually lose.

b) Give a written literate translation of the text.

Стрелка вправо 91