If you brush your teeth you will keep your teeth healthy.

People also cleaned their teeth thousands of years ago.

Someone had eaten something sticky. 

He rubbed the fuzzy end of a twig against his teeth.

Toothpaste was invented hundreds of years later.

Someone invented something that looked more like today’s toothbrush.

He attached the bristles to a handle made from animal bone.

People still tried to improve the tooth cleaner.

Later, man‐made bristles were made.

Plastic was used for handles.

Millions of toothbrushes were sold.

The electric toothbrush was invented much later.

We have toothbrushes with different bristles now.

The toothbrush has improved a lot since chew sticks.

Sometimes people accidentally invent something.

Post-its are used for marking your place on a book page.

He thought: ‘I really need a way to keep these notes in.’

He came up with a good idea.

He invented a new kind of bookmark.

An adhesive was put on the paper instead of the board.

The adhesive they used wasn’t good enough.

They improved the glue on the paper.

They had to make sure that the paper wouldn’t fall off.

The sticky papers were called Post-its.

There are different sizes and colours Posts-its.

Post-its can also be used to make art works.