We divide all the building materials into three main groups.

A) All the building materials are divided into three main groups.

The builders use binding materials for making artificial stone.

A) Binding materials are used for making artificial stone.

People knew bricks many thousands of years ago.

A) Bricks were known many thousands of years ago.

The architect designs houses to provide more sun and air for living rooms.

A) Houses are designed to provide more sun and air for liviing rooms.

They employ different workmen in building a house.

A) Different workmen are employed in buildng a house.

We divide all metals into ferrous and non-ferrous metals.

A) All metals are divided into ferrous and non-ferrous metals.

The cars and heating systems pollute air.

A) Air is polluted by heating systems and the cars.

We call bronze an alloy of copper and tin.

A) An alloy of copper and tin is called bronze.

An architect must carefully plan every detail of a house.

A) Every detail of the house must be carefully planned.

The builders build tunnels, canals, power stations, dams and reservoirs.

A) Tunnels, canals, power stations, dams and reservoirs are built.

A carpenter does the rough woodwork of the house.

A) The rough woodwork of the house is done by a carpenter.

Plumbers work on all the water pipes of the house.

A) All the water pipes of the house are worked on by plumbers.

Builders now produce two types of new building matrials.

A) Two types of new building matrials are produced by builders.

We use stainless steel for cutlery, valves, chemical plant equipment, etc.

A) Stainless steel is used for cutlery, valves, chemical plant equipment, etc.

The workmen use the concrete to fill in the bottom of the trenches.

A) The concrete is used to fill in the bottom of the trenches.

A) Concrete and stone are used for the construction of walls.

A) Plans for building a house are drawn by an architect.

The joiners finish all the woodwork in the house.

A) All the woodwork in the house is finished by joiners.

A) A lot of strong timber which we cannot see is used to make a roof.

Plumbers also lay pipes to carry waste water away to the sewers.

A) Pipes are laid to carry waste water away to the sewers.

Choose the correct variant.

The foundation work …. by providing anchoring sills.

A) is finished

The column … an important part in the history of building since the earliest day.

A) has played

Quite a lot of people all … together to make the house.

A) work

The spaces between the foundations walls … with concrete.

A) are filled

Aluminum alloys... the strength of steel.

A) can possess

The bricks … together with mortar.

A) are stuck

The elevators … moving staircases.

A) are like

Steel and cast iron … to the group of ferrous metals.

A) are referred

The principal virtues of aluminium … lightness combined with strength.

A) are

The basic materials for making concrete … cement, aggregate and water.

A) are

We … all metals into ferrous and non-ferrous metals.

A) divide

Copies of the plan... and are given to the builder.

A) are made

The characteristics of concrete … upon the quality of the materials.

A) depend

All types of cement … during setting.

A) shrink

What … when water is added to the cement?

A) takes place

The water used for mixing cement, lime and plasters … reasonably clean.

A) must be

On tall buildings the builder... a lift which can be moved to different places.

A) may use

Air pollution problem … in the near future.

A) won’t be solved

The durability of sandstones … very largely upon the cementing material.

A) depends

What kind of masonry units …?

A) do you mean

The builders … to continue their work, because it was so late.

A) weren’t able

Houses... of wood, bricks, stone and concrete.

A) are built

Without water a man soon …

A) perishes

Plastics … all the fine characteristics of a building material with good insulating properties.

A) combine

We … many building materials for bearing structures.

A) use

Into what two classes can concrete …?

A) be divided

Olympic Committee … much attention to sports and games.

A) pays

A lot of work... by builders in near feature.

A) will be done

Our country … more and more specialists with a higher education nowadays.

A) requires

Builders now … two types of new building materials.

A) produce