题目内容：

Some plants can produce bad smell to protect themselves. Also some plants have thorns(刺) as roses. The leaves of some plants can change colour. Some plants can eat insects！

Lots of animals try to eat plants. But some plants have their ways of fighting back. For example, thistles(奶蓟草), roses, and many other plants are covered with sharp thorns.When a big animal tries to bite them, it hurts!

It can be quite cold in late winter―too cold for most flowers to grow. But some plants can make their own heat

Take a skunk cabbage(臭菘).That's the name of a plant that blooms(开花)earlier than most other North American flowers. As the flower bud grows, it sometimes makes enough heat to melt(融化)its way through snow and even ice!

The heat also helps the flower give off a smell like meat which has gone bad. And this attracts many insects that have come out early. The flies go inside the flower for food. Ha-ha, it's a trick! There's no food. But while a fly is in there, it gets covered with pollen(花粉).Then it may spread this pollen to the next skunk cabbage. Fooled you twice, little fly!

When an antelope(羚羊)or another large animal eats the leaves of an African acacia(金合欢)tree, the tree may call out a warning.

How? It may talk with gas! First the tree sends some chemicals into its leaves to make them taste bad. But it also may send a special gas out through its leaves. As the gas drifts to other acacia trees, it "tells" those trees, "Look out, hungry animals are coming !" Then the other trees start sending the chemicals into their leaves. Soon, the antelope finds the first tree's leaves too terrible to eat. And when it moves to the next tree, and the next, and the next, it finds that their leaves taste too bad. The antelope may have to walk more than 50 yards away to find a tree it can eat!

1.How does a thistle protect itself?

A. Its leaves can change colour.

B. It can grow right up through the hard road.

C. Its sharp thorns can hurt big animals.

D. Its leaves are not delicious at all.

2.The skunk cabbage can give off a smell like bad meat in order to       .

A. melt the snow and even ice

B. attrart insects to spread pollen from flower to flower

C. kill the`flies going inside the flower

D. fool the flies twice for fun

3.Which is the right order of the following statements?

a. The leaves of the acacta tree give away a special gas.

b. The antelope comes to eat the leaves of the acacia tree.

c.The other trees also make their leaves not good to eat.

d.The antelope goes away after trying leaves of the next tree.

A. b-a-c-d    B. c-d-a-b    C. b-c-a-d    D. a-c-b-d

4.In what way does the writer tell us how plants-can protect themselves?

A. By using a few numbers.

B. By telling stories one after another.

C. By following the order of time.

D. By giving examples.

5.The passage is mainly about        .

A. the importance of protecting forests

B. the balance between animals and plants

C. the ways of plants fighting against enemies

D. the relationship between plants and animals