阅读理解。 High in the mountains, and deep i

题目：

阅读理解。

    High in the mountains, and deep in the forest, lives a lake with many plants and animals in and around

her. The plants and animals have enough food and clean water to keep them healthy. The wind carries

pure air, and the rain comes down clear and clean.

    But recently, Lucy Lake and her friends haven't been feeling very well. All the plants and animals get

together to talk about the problem. "Why are we sick?" "What can we do?" ask all of them. No one has

any answers.

    Just then two hikers appear. The animals tell them about their problems. "Can you help us?" they ask.   

     "Yes," one hiker says. "I think it's because of acid rain."

    "Acid rain comes from chemicals(化学物质) in the air. The pollution comes from factories, cars and

trucks."

    "So, although I don't want to, I help the pollution travel through the air!" says the wind. "And I carry it

to the land!" cries the rain.  

    "If you can help us think of some solutions(解决方法), we will send a message to tell people how to

clean up our environment," one hiker says.  

    With the help of the plants and animals, the two hikers make a list of ideas for saving Lucy Lake and

her friends.

    Time passes, and the forest and lake begin to feel a little better.

    The next time the hikers climb up the mountains to Lucy Lake, they smile at what they find. "We're

glad things have started to change," one hiker says. "And we're glad you helped us make a difference,"

says the other.

1. The underlined word "pure" can be replaced by "____".

A. polluted

B. clean

C. cold

D. cool

2. The two hikers are most probably ____.

A. scientists

B. teachers

C. doctors

D. reporters

3. ____ have (has) nothing to do with the cause of acid rain.

A. The rain  

B. Human beings

C. The wind  

D. The plants and animals

4. The underlined word "you" refers to (指) ____.  

A. Lucy Lake

B. the plants and animals    

C. one of the two hikers

D. the wind and the rain

5. Which of the following is NOT true?

A. Acid rain is very harmful only to plants and animals.

B. Human activities are the main cause of acid rain.

C. Acid rain can make the living things in the environment get sick.

D. We should clean up our environment to protect us against acid rain.