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10 Fill in the gaps with derivatives of the words in capitals:

To avoid decay and termite 1) _____, it is important to separate 2) _____ wood from the ground and other sources of moisture. These separations are required by many 3) _____ codes and are considered necessary to maintain wood elements in permanent structures at a safe moisture content for decay 4) _____. When it is not possible to separate wood from the sources of moisture, 5) _____ often rely on preservative-treated wood.

Wood can be treated with a preservative that improves service life under severe conditions without 6) _____ its basic characteristics. It can also be pressure-impregnated with fire-retardant chemicals that improve its performance in a fire.

Wood does not deteriorate just because it gets wet. When wood breaks down, it is because an organism is eating it as food. Preservatives work by making the food source inedible to these organisms. 7) _____ preservative-treated wood can have 5 to 10 times the service life of untreated wood. Preserved wood is used most often for railroad ties, utility poles, marine piles, decks, fences and other outdoor applications. Various 8) _____ methods and types of chemicals are available, depending on the attributes required in the particular 9) _____ and the level of protection needed.

There are two basic methods of treating: with and without 10) _____. Non-pressure methods are the application of preservative by brushing, spraying or dipping the piece to be treated. Deeper, more thorough penetration is achieved by driving the preservative into the wood cells with pressure. Various combinations of pressure and vacuum are used to force adequate levels of chemical into the wood.

INFEST

TREAT

BUILD

PROTECT

DESIGN

ALTER

PROPER

TREAT

APPLY

PRESS

11 Fill in the gaps in the following passage with a suitable preposition given below:

between of(x3) into for in with to

Under microscopic investigation, softwoods show only one type 1) _____ cell which varies 2) _____ size 3) _____ the rapid growth 4) _____ spring and early summer (early wood) and the slow growth 5) _____ the late summer and autumn (late wood). These cells perform the food- and water-conducting functions and give strength 6) _____ the tree. Hardwoods, however, have a more complex cell structure 7) _____ large cells 8) _____ the conducting functions and smaller cells providing the mechanical support. They can be divided 9) _____ two distinct groups: diffuse-porous hardwoods and ring-porous hardwoods (Fig. 5.2).

Softwood –

Scots Pine

Diffuse-porous hardwood – Birch

Ring-porous

hardwood – Oak

Figure 5.2 Cell Structure

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1. деревянные части здания. 2. рельеф. 3. кирпич. 4. электророзетка. 5. выключатель. 6. водопроводчик. 7. оконная рама. 8. сосна. 9. герметичный. 10. желобок. 11. петля дверная, оконная. 12. ручка дверная, оконная.

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