50. Air pollution is the most serious kind of pollution because       .

A. it’s bad to all living things in the world

B. it makes us become angry more easily

C. it has made our rivers and lakes dirty

D. it makes much noise

51.  Which of the following is NOT true?

A. The problem of pollution is not so serious because there are not so many people.

B. From now on, people should try to go to work by bus or bike instead of car or motorbike.

C. The pollution of the earth grows as fast as the world’s population does.

D. Many countries are making rules to fight pollution.

(C)

An 8-year-old child heard her parents talking about her little brother Andrew. All she knew was that he was very sick and they had no money. Only a very expensive operation could save him.

One morning, the girl heard her father say to her mother, “ Only a miracle can save Andrew now.” The girl went to her bedroom, collected all of her money and counted all of her money and counted it carefully. She hurried to a drugstore(药房).

“How can I help you?” asked the salesman.

“I want to buy a miracle,” the girl answered. “My brother has something bad growing inside his head. My daddy says only a miracle can save him. So how much does a miracle cost?”

“We don’t sell miracles here, my dear. I’m sorry,” the salesman said, sadly.

“What kind of a miracle does your brother need?” asked a well-dressed man standing nearby.

“I don’t know,” she answered. “He’s really sick and needs an operation in his head. So I brought all my money.”

“How much do you have?” asked the man.

“$1.1,” she answered.

“Well, what luck,” said man. “$1.1 is the price of a miracle. Let’s go to see your brother.”

That man was Dr Carlton Armstrong, a famous brain doctor. The operation was successful and it wasn’t long before Andrew was well again. Sometimes miracles do happen.

52. The girl hurried to the drugstore       .

A. to buy some medicine for her parents

B. to ask the salesman to buy a miracle for her

C. to ask someone to help her brother

D. to buy something called a “miracle” for her brother

53. Why did the man say “$1.1 is the price of a miracle”?

A. Because a miracle just cost $1.1.

B. Because he wanted to sell more miracles.

C. Because he was moved by the girl.

D. Because he didn’t know the real price.

54. Andrew was well again because       .

A. his parents made enough money

B. his sister bought some medicine for him

C. a famous brain doctor helped him

D. his sister did an operation on him

55. From the passage, we learn that      .

A. miracles may happen when there is love

B.$1.1 is the right amount(数目)of money to buy a miracle

C. We can buy miracles in drugstore

D. Miracles can be found everywhere