passive voice unit 9

Companies use aluminium to make bicycles these days because it is lighter than other metals.

Aluminium

People collect coins from countries around the world, particularly if they are rare.

Coins

Criminals have stolen copper from many buildings in London because of its value.

Copper

A miner found gold in Australia in 1851.

Gold

People often give leather items as a third wedding anniversary present.

Leather items ..................................................................

People won’t need paper to write on in the future.

Paper

In the past, people built their houses with local stone.

In the past, houses

(how many / emails / send / every day) ?

More than 145 billion, and this number is growing every year.

(why / the Great Wall of China / build) ?

To protect the border. It is the longest man-made structure in the world!

(where / the next Olympic Games / hold) ?

Oh, I’m not sure!