48. Form the nouns from the following verbs.

to distribute →…	to circulate →…	to deliver →…
to condense →…	to expose →…	to equalize →…
to affect →…	to install →…	to convert →…
to force →…	to resist →…	to provide →…

49. Match the terms with their definitions.

a) boiler	e) furnace	i) thermostat
b) filter	f) pump	j) cable
c) duct	g) radiator	k) current
d) humidifier	h) convector	l) shield

1. a passage through which air can flow, as in air conditioning;

2. an enclosed chamber in which heat is produced to generate steam, destroy refuse, smelt or refine ores, etc;

3. a device for filtering particles from the air passing through it, especially one protecting the air inlet of an internal-combustion engine;

4. a device for increasing or controlling the water vapour in a room, building, etc;

5. a space-heating device from which heat is transferred to the surrounding air by convection;

6. a closed vessel or arrangement of enclosed tubes in which water is heated to supply steam to drive an engine or turbine or provide heat;

7. any device for compressing, driving, raising, or reducing the pressure of a fluid, esp by means of a piston or set of rotating impellers;

8. a device for heating a room, building, etc., consisting of a series of pipes through which hot water or steam passes;

9. any similar protective device;

10. a flow of electric charge through a conductor;

11. a strong thick rope, usually of twisted hemp or steel wire;

12. a device that maintains a system at a constant temperature. It often consists of a bimetallic strip that bends as it expands and contracts with temperature, thus breaking and making contact with an electrical power supply.

50. Fill in the correct prepositions, translate the phrases, then choose any five items and make up the sentences of your own.

1) to differ ___ the way; 2) to circulate steam ___ pipes; 3) to give ___ heat; 4) to warm the air ___ a furnace; 5) to force air ___ a system of pipes ___ each room; 6) to carry air ___ the rooms back ___ the furnace; 7) to remove dust particles ___ the air; 8) to add moisture ___ the air; 9) to increase the humidity ___ the home; 10) to have certain advantages ___ smth.; 11) a network ___ pipes; 12) to depend ___ a shape; 13) the air ___ knee height, ___ the ceiling and ___ floor level; 14) too cold ___ comfort; 15) to equalize temperature ___ a room; 16) to be installed ___ the skirting boards of a room; 17) to limit the temperature difference ___ the floor and the ceiling ___ only a few degrees; 18) to produce electricity ___ nuclear energy; 19) to produce heat ___ passing electricity ___ a material; 20) to produces heat ___ electricity; 21) to be controlled ___ thermostats.