Main Idea

Front

What did people use to clean their teeth before toothbrushes were invented?

Back

People used natural objects like small twigs to clean their teeth.

Front

What are the bristles of most toothbrushes made from today?

Back

Most toothbrushes are made from nylon.

Front

What is the main idea of the sentence: 'Sharks have a lot of teeth.'?

Back

Sharks have a lot of teeth.

Front

What is the cause in the sentence: 'Because it rained, I got soaked.'?

Back

It rained.

Front

What do beavers create when they build a dam across a river?

Back

Beavers create a pond or even a lake.

Front

What happens to land that was once dry when beavers build a dam?

Back

It gets covered in water.

Front

What is the effect of the rain in the sentence: 'Because it rained, I got soaked.'?

Back

I got soaked.

Front

What is the main idea of the sentence: 'Beavers make dramatic changes to the environment.'?

Back

Beavers make dramatic changes to the environment.

Front

How many teeth can a shark have at one time?

Back

A shark may have up to 3,000 teeth at one time.

Front

What happens when a shark loses a tooth?

Back

It is replaced by a new tooth from the row behind it.