Read the text and (a) - headline it

(b) - translate it into Russian using a dictionary.

The rapid rise in population and land values in urban areas combined with today ever improving standards of living, stimulates centrally air -conditioned high rise building construction. There are many variations of air-conditioning systems applicable to a given building. In the past, the choice centered around the least construction cost and least professional fees. Very little attention was given to effective energy use. As a result, many commonly used standard air-conditioning systems have poor efficiencies. It was generally thought an energy efficient system increased construction cost.

In recent years, due to the energy shortage and a tight economy, new systems and technology have been introduced to the building industry that can save energy without increasing construction cost.

THEME 3.

PRINCIPLES OF AIR - CONDITIONING.

1. Answer the questions:

1. In what century was air - conditioning first used for comfort?

2. What country was the first to use air - conditioning installations?

3. What was first air - conditioned - homes or public places?

2. Read the text and say if it has something in common with the contents of text on the history of air - conditioning, in what way it en­riches it.

Mind the unknown words: