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Have you ever seen a horse with toes(腳趾)？Millions of years ago, horses had many toes. They had four toes on each front foot. They had three toes on each back foot. The horses were no bigger than the cats.These small horses lived in the forest. The toes helped the horses run on the soft, wet ground.

At first, it was very hot in the forest. But the weather changed. It became very cold. Many trees could not live in cold weather. The trees died and fell. Open fields took the place of forests. The sun made the ground dry and hard.

Horsed began to change, too. They began to get bigger. This took a long time. On the dry, hard land, horses needed only their middle toes for running. Their middle toes became hard. After a long time, horses had only one hard toe on each foot. Now we call this hard toe a hoof.

1.How many toes did a horse have millions of years ago?

A．14               B．12               C．16               D．13

2.What does the underlined word “hoof” mean in Chinese?

A．尾巴             B．馬鬃             C．腿               D．蹄子

3.What was the weather like in the forest at first?

A．Very warm         B．Very hot           C．Very cold          D．Very cool

4.Which is WRONG according to the passage?

A．The horses were much bigger than the cats millions of years ago.

B．The trees died and feel because the weather changed.

C．On the dry, hard land, horses needed only their middle toes for running.

D．The horses have fewer toes than before.

5.The main idea of the passage is that_______________.

A．horses had three toes on each back foot.     B．horses lived in the hot forest

C．horses changed a lot over the years         D．horses didn’t like the cold weather