1. Choose the correct sentence in Passive Voice.

A) A lot of houses are built of fabricated blocks.

A) The man who builds walls is called a bricklayer.

A) The walls of the house will be built on the concrete foundations.

A) They are ready to be fixed in the houses.

A) Water is purified by mechanical and biological methods nowadays.

A) Water and air pollution problems will not be solved in the near future.

A) Walls may be either covered with wall-paper or only plastered.

A) Steel and cast iron are referred to the group of ferrous metals.

A) Concrete can be divided into two classes.

A) Materials that are used for structural purposes should meet several requirements.

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.