Work your brain!

   Between 2 and 3 pounds of wonder, it controls everything we say, do or think, who we are and what we care about. The way we walk or laugh or figure out things. What we like and the talents we possess. How we see and talk and run and jump and process our food.

    The brain uses 20 percent of our body’s oxygen and 20 percent of its blood. Somewhere within its protein, fat, 100,000 miles of blood vessels and 100 billion nerve cells, it helps us remember where we put our gym shoes. Change our temperature so we don’t die because of the heat or cold. Speed us up or slow us down. Help us choose between orange juice or orange­flavored drinks.

    Its complexity are stunning, far beyond anything most of us can imagine. To keep this work of art as polished as possible we need to eat right, exercise and keep mentally stimulated. Good nutrition helps brain cells communicate with each other. Exercise stimulates a hormone in our brain that improves memory. Mental stimulation keeps you sharp even as you age.

“It’s very important that we tell people to be physically active and mentally active,” said neurologist Malcolm Stewart.“People cannot stop aging, but you’re able to reduce the damage; you’re able to keep the function up.”

Following are Dr. Stewart’s advice for improving brain health：

1.The purpose of the author in writing this passage is to ______.

A. inform us how the brain works

B. give us advice on how to keep the brain healthy

C. tell us that the brain plays an important role in our lives

D. show how special the brain is to us

2.The underlined word “stunning” means ______.

A. interesting 　               B. strange                          C. significant　                  D. amazing

3.According to the text，more exercise ______.

A. keeps our mind sharp             

B. helps improve our memory

C. gives our brain a rest 　           

D. is good for brain cells communicating with each other

4.In order to keep brain healthy，we should avoid ______.

A. eating a good lunch                                     B. doing puzzles

C. eating a large supper                                  D. taking aerobic exercise

Work your brain!

Between 2 and 3 pounds of wonder，it controls everything we say，do or think，who we are and what we care about. The way we walk or laugh or figure out things. What we like and the talents we possess. How we see and talk and run and jump and process our food.

The brain uses 20 percent of our body's oxygen and 20 percent of its blood. Somewhere within its protein，fat, 100,000 miles of blood vessels and 100 billion nerve cells，it helps us remember where we put our gym shoes. Change our temperature so we don't die because of the heat or cold. Speed us up or slow us down. Help us choose between orange juice or orange­flavored drinks.

Its intricacies(复杂性)are stunning，far beyond anything most of us can imagine. To keep this work of art as polished(有光泽的) as possible we need to eat right，exercise and keep mentally stimulated(刺激)．

Good nutrition helps brain cells communicate with each other. Exercise stimulates a hormone(荷尔蒙)in our brain that improves memory. Mental stimulation keeps you sharp even as you age.

“It's very important that we tell people to be physically active and mentally active，” said neurologist Malcolm Stewart.

“People cannot stop aging，but you're able to reduce the damage；you're able to keep the function up.”

Following are Dr.Stewart's advice for improving brain health：

1.The purpose of the author in writing this passage is to ______.

A. inform us how the brain works

B. give us advice on how to keep the brain healthy

C. tell us that the brain plays an important role in our lives

D. show how special the brain is to us

2.The word “stunning” in Paragraph 5 means ______.

A. interesting 　       B. strange              C. significant　        D. amazing

3. According to the text，more exercise ______.

A. keeps our mind sharp 　　 

B. helps improve our memory

C. gives our brain a rest 　　 

D. is good for brain cells communicating with each other

4. In order to keep brain healthy，we should avoid ______.

A. eating a good lunch                      B. doing puzzles

C. eating a large supper                    D. taking aerobic exercise

　　Both warm-blooded and cold-blooded desert animals have ways to escape the desert heat. Warm- blooded desert animals, such as rats and mice, rest during the day, often staying in cool underground burrows. At night they search for food. Animals that are out during the day, such as cold-blooded lizards and snakes, are active only for short periods. As their body temperature rises, these reptiles（爬行动物） move into the shade in order to cool down. In the early evening, when the sun grows weaker, the reptiles become more active and begin their search for food again.

　　Getting enough water to survive is a major problem for all desert animals. Some desert animals, like desert birds, manage to find water holes. Other desert animals, such as the kangaroo rat and the related jerboa, get water only from the food that they eat. Because these animals eat mainly dry seeds, they must survive on a tiny amount of water.

　　Most deserts have only a small number of frogs and toads because these animals must be near water to survive. Yet even these creatures have adapted(适应) to desert conditions. When small amounts of water collect in temporary streams, the desert-living frogs and toads become active. After a rainfall, they lay their eggs. The eggs grow into tadpoles in a few days and into adults in just four weeks. When the puddles(水坑) dry up, the adult frogs or toads dig into the ground. Their metabolism(新陈代谢) slows, and they stay beneath the ground until the next rain, which may be as good as a year away. Until then, their bodily activities continue at a reduced rate.

　　The camel ― often called the ship of the desert ― is one of the most successful desert animals. Camels can go for long periods without water, but eventually they must drink. When water becomes available to them after a long drought, they may drink 95 liters of water or more. When water is not available, what helps camels survive the desert heat is the fat stored in their humps(驼峰). A camel’s hump contains about 12 kilograms of fat. Fat is rich in hydrogen. As the fat is digested, hydrogen from the fat combines with oxygen in the air that the camel breathes. The result is H2O, or water. Each kilogram of fat that a camel digests produces about a liter of water.

41. Desert animals are usually more active at night because _____.

　A. it is cooler at night        B. it is easier to find water

　C. they like the dark         D. they are less likely to be attacked at night

42. Which of the following desert animals can get water only from the food?

　A. The camel.     B. The kangaroo.     C. The frog.    D. The rat.

43. Which of the following is TRUE according to the passage?

　A. All the desert animals rest during the day.

　B. All the desert animals don’t rest during the day.

　C. Cold-blooded desert animals are out most of the day.

　D. None of the cold-blooded desert animals go out during the day.

44. The title for this passage could probably be _____.

　A. Hot Deserts                            B. Desert Animals

　C. How Desert Animals Get Water            D. Ways To Escape the Desert Heat

45. The underlined word “burrows” in the first paragraph can be replaced by _____.

　A. holes        B. caves       C. rooms        D. openings

When I was in my early twenties，I moved away from my home state of Wisconsin to attend graduate school．I chose to go to the University of Arizona in Tucson and 　36 there．Upon landing in early June，I was shocked by the lack of　 37　 and the burning desert heat． After less than two days in that 38　 ，I called my parents to question whether I had made the　 39　 choice and to announce that I was 　40　 considering coming home．My father，in a calm and　 41　 voice，indicated that I always had a 　42 ． I could always come home and be welcome there．But in fact，we both 　 43 I wouldn’t come home at the time．Needless to say，I chose to　 44 ．　　　　　

Many years have passed． My father’s 　45　 words remain with me．Knowing that I can always 　 46 ，I’ve been able to 　47　 several challenging situations-unemployment，divorce and even the 　48　 of my only son．I have also used these words in many cases where others need to know that someone 　 49　 and that they do have a choice．

Whether 　50 is earthly，spiritual，or some sense of calm，knowing that we can come home will be just enough to　 51　 us on our way．

It 　 52 me, in a way, of the prodigal son（回头的浪子）who found 　53　 and love upon returning home．While we don’t have to be like him and hit bottom in life，it is good to know that we can wander and experience pains and　 54 in life but we still have a home where love，support and comfort 　 55 .

36．A．flew　　　　　 　 B．drove　 　　　　　　　 C．walked　　　 　　　 D．cycled

37．A．blue　　　　 　　 B．yellow　 　　　　　　　 C．brown　　　　 D．green

38．A．university　　　 　 B．school　 　　　　　　　 C．environment　 　　 D．desert

39．A．new　　　　 　　 B．right　 　　　　　　　 C．last　　　　 　　　　 D．difficult

40．A．naturally　　 　　　 B．fortunately　 　　　　 C．obviously　　 　　　 D．seriously

41．A．gentle　　　　 　 B．weak　　　　 　　 C．supportive　 　　　 D．pleasant

42．A．choice　　 　　　　 B．dream　　　　 　　 C．friend　　　 　　　 D．request

43．A．pretended　　 　　 B．expected　　 　　　 C．knew　　　　 　 D．forgot

44．A, graduate　 　　　　 B．regret　　　 　　　 C．return　　　 　　　 D．continue

45．A．surprising　　　 B． encouraging　 　　 C．interesting　 　　　　 D．moving

46．A．wander outside 　 B．hang around　 　　　 C．come home　　 　 D．move away

47．A．face up to　 　　　 B．get away with　 　 C．make sure of　 　　 D．look out for

48．A．return　　　 　　　 B．growth　　　　 C．arrival　　　 　　 D．loss

49．A．worries　　　 　　 B．cares　　　　　 　 C．leaves　　　　 　　 D．stays

50．A．health　　　 　　　 B．marriage　　　 　 C．church　　　　 　 D．home

51．A, help　　　　　　 B．stop　　　　　 　 C．protect　　　 　　 D．teach

52．A．informs　　　 　　 B．reminds　　　 　 C．warns　　　　 　 D．rids

53．A．comfort　　　 　　 B．interest　　　 　　 C．food　　　　　 　 D．money

54．A．regrets　　　　 　 B．complaints　　 　 C．sufferings　　 　　 D．pleasures

55．A．survive　　　 　　　 B．exist　　　　　 　 C．fall　 　　　　　　 D．disappear