It is difficult for doctors to help a person with a damaged brain. Without enough blood, the brain lives for only three to five minutes. More often the doctors can’t fix the damage. Sometimes they are afraid to try something to help because it is dangerous to work on the brain. The doctors might make the person worse if he operates on the brain.
Dr. Robert White, a famous professor and doctor, thinks he knows a way to help. He thinks doctors should make the brain very cold. If it is very cold, the brain can live without blood for 30 minutes. This gives the doctor a longer time to do something for the brain.
Dr. White tried his idea on 13 monkeys. First he taught them to do different jobs, then he op­erated on them. He made the monkeys’ blood go through a machine. The machine cooled the blood. Then the machine sent the blood back to the monkeys’ brains. When the brain’s tempera­ture was 10°C, Dr. White stopped the blood to the brain. After 30 minutes he turned the blood back on. He warmed the blood again. After their operations the monkeys were like they had been before. They were healthy and busy. Each one could still do the jobs the doctor had taught them.
【小题1】The biggest difficulty in operating on the damaged brain is that _______.

__  Mr. Jones called while you were out. He was in _____ very bad temper

1. A.
   / ; a
2. B.
   A; /
3. C.
   The; the
4. D.
   A; a

The nurse was very kind to the boy at first, but finally, her ____ gave out and she lost her temper

1. A.
   patience
2. B.
   violence
3. C.
   presence
4. D.
   independence

　　Destructive insects in larger numbers are finding Alaska forests to be a comfortable home and climate change could be the wel-come mat.

　　Warmer winters kill fewer insects. Lon-ger, warmer summers let insects complete a life cycle and reproduce in one year instead of two. Warm winters also can damage trees and make them less able to stop insect attacks by changing the nature of snow. Instead of light snow formed at extremely cold tempera-tures, warm winters produce wet, heavy snow more likely to break the tops of spruce trees because they are not well adapted to handling big, heavy, wet snow loads.

　　Since 1980, spruce bark (树皮) beetles have killed mature white spruce trees on 4. 4 million acres. For lack of two cold winters on end, the numbers of the beetles there blew up while the resistance (抵抗力) of the trees was down at the same time everywhere. Most of the mature trees have been killed in some whole region of the state.

　　Spruce bark beetles bore into (蛀穿)trunks and feed on the live cambium layer, a thin part of tissue between bark and wood. Trees re-sist beetles with pitch, made up of hydrocarbons including up to 17 forms of terpene (松稀). The rates of those terpenes are a signal of the health of the tree. When a tree is injured, terpene rates go off in one direction.

　　Using complex chemical receptors (感受 器), spruce bark beetles discover differences in terpenes. Injured trees offer less resistance.

　　They smell the tree. If the tree's healthy,they try to avoid it Why? If they start to bore into a healthy tree, it's got a lot of pitch, and the pitch is under high pressure. It's boring in and the pitch is pushing it back out.

(1) What would be the best title for the text?

[　　]

A．The Destruction of Forests in Alaska

B．Warm Winters and Its Bad Effects

C．The Way of Spruce Trees' Living in Alaska

D．Destructive Insects on Rise in Alaska

(2) According to the text, how do warm win-ters reduce the trees' ability to resist in-sect attacks?

[　　]

A．By changing the nature of snow.

B．By offering too much water to trees.

C．By making the weather drier.

D．By increasing the insects' growth speed.

(3) The third paragraph mainly tells________.

[　　]

A．winters are warmer and warmer

B．there are more and more beetles

C．the situation of trees is much worse

D．mature trees are easy to be attacked

It is difficult for doctors to help a person with a damaged brain. Without enough blood, the brain lives for only three to five minutes. More often the doctors can' t fix the damage. Sometimes they are afraid to try something to help because it is dangerous to work on the brain. The doctors might make the person worse if he operates on the brain.

Dr. Robert White, a famous professor and doctor, thinks he knows a way to help. He thinks doctors should make the brain very cold. If it is very cold, the brain can live without blood for 30 minutes. This gives the doctor a longer time to do something for the brain.

Dr. White tried his idea on 13 monkeys. First he taught them to do different jobs, then he op­erated on them. He made the monkeys' blood go through a machine. The machine cooled the blood. Then the machine sent the blood back to the monkeys' brains. When the brain’s tempera­ture was 10°C, Dr. White stopped the blood to the brain. After 30 minutes he turned the blood back on. He warmed the blood again. After their operations the monkeys were like they had been before. They were healthy and busy. Each one could still do the jobs the doctor had taught them.

1. The biggest difficulty in operating on the damaged brain is that _______.

A. the time is too short for doctors              B. the patients are often too nervous

C. the damage is extremely hard to fix  D. the blood-cooling machine might break down

2. The brain operation was made possible mainly by _______.

A. taking the blood out of the brain             B. trying the operation on monkeys first

C. having the blood go through a machine D. lowering the brain' s temperature

3. With Dr. White’s new idea, the operation on the damaged brain _______.

A. can last as long as 30 minutes            B. can keep the brain' s blood warm

C. can keep the patient’s brain healthy        D. can help monkeys do different jobs

4. What is the right order of the steps in the operation?

a. send the cooled blood back to the brain

b. stop the blood to the brain

c. have the blood cooled down

d. operate on the brain

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