In 1963,former Senator Gaylord Nelson began to worry about our planet (A senator is a person that the people of the United States have chosen to help make the laws.). Senator Nelson knew that our world was getting dirty and that many of our plants and animals were dying .He wondered why most people weren’t trying to solve these problems. He talked to other lawmakers and to the President. They decided that the President would go around the country and tell people about these concerns（关系重大之事）. He did, but still not enough people were working on the problem.
Then, in 1969, Senator Nelson had another idea. He decided to have a special day to teach everyone about the things that needed changing in our environment .He wrote letters to all of the colleges and put a special article in Scholastic Magazine to tell them about the special day he had planned (Most of the schools got this magazine) and he knew that kids would help him.
On April 22,1970, the first Earth Day was held .People all over the country made promises to help the environment. Everyone got involved and since then, Earth Day has spread all over the planet. People all over the world know that there are problems we need to work on and this is our special day to look at the planet and see what needs changing. Isn’t it great? One person had an idea and kept working until everyone began working together to solve it. See what happens when people care about our world?
【小题1】The passage mainly talks about _________.

C
An oasis (绿洲) is an island of life in an ocean of temperature extremes．Any oasis always contains one or more springs Oases make it possible to survive through the desert．In large deserts such as the Sahara．towns are located around sources of water such as oases and rivers．
What causes an oasis? An oasis is actually a spot in the desert where the altitude is low enough that the water table is fight below the surface，resulting in the presence of springs．Even in a desert, it rains occasionally，and this produces a water table just above the bedrock，usually several hundred feet below the surface．Sand is very porous (可渗透的)，so most water runs right
through it and down to the bedrock．
Deserts consist of many millions of tons of sand．There is only one natural force capable of moving it in noticeable amounts：the wind．Although，in an average dust storm，ten cubic feet of air only holds about an ounce of sand，a cubic mile of air can move about 4,600 tons of it，leading to erosion (侵蚀)．A severe storm is capable of moving as much as 100 million tons of sand and dust．
In certain areas where large quantities of sand are moved by storms，erosion digs all the way down to the water table，putting it just beneath the surface Seeds planted in the ground there are capable of extending roots into the moist land，producing an oasis．
Sometimes．the oasis produced by the wind can be very large when vast tracts of desert are wiped clean by storms．The great Kharga oasis in the Sahara，for example，is over 100 miles long and 12 to 50 miles in width. The oasis was produced when erosion caused the edges of the hollow places to sink down to the water table.    
63．What does “it” in Paragraph 4 refer to_______．
A．erosion        B．water table          C．sand                      D．storm
64．How many conditions of the oasis formation are mentioned in the passage without considering
The wind and seeds?
A．3                B．4                        C．5                           D．6
65．We can infer from the passage ________．
A．there is at least one spring on an oasis
B．the bedrock is usually just right below the surface
C．the great Kharga oasis is the biggest oasis in the world
D．the great Kharga oasis is at a low altitude
66．In the last paragraph，the author mentions the great Kharga oasis as an example to_______．
A．introduce the great oasis to the readers
B．tell how the oasis was produced by rain
C．show the oasis produced by the wind can be very large
D．tell it’s easy to form oases in the desert after storms

A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.
Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.
Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳动物) have unexpectedly been discovered in the skin of mice.
“No one had ever looked,” explained Randall Johnson, a biologist researcher.
Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.
“We have no reason to think that they are not in the skin of people too,” Johnson said.
These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen—a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.
These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a multibillion-dollar market, Johnson said.
Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however—there’s a lot we don’t know yet,” Johnson explained.
The scientists detailed their findings in the April 18 issue of the journal Cell.
【小题1】Which of the following statements is TRUE according to the passage?

A little boy was spending his Saturday morning playing in his sandbox. While creating roads in the soft sand, he   36  a large rock in the middle of the sandbox.

The boy   37  around the rock, managing to move it out from the dirt. With much   38 , he tried to push the rock out of the sandbox. When the boy got the rock to the edge(边缘) of the sandbox,   39 , he found that he couldn’t   40  it up and over the little wall. The rock was too   41  for his small body.

As he   42  to accept his failure, the little boy dug, pushed, and pried(撬动), but every time he thought he had made some   43 , the rock rolled and then fell back into the sandbox. The little boy   44  again and again, but the only   45  was to have the rock roll back.

  46 , he burst into tears. All this time the boy’s father   47  him from his living room. The moment the tears fell, a   48  voice rose above the boy’s head. It was his father.  49 , but firmly(坚定地) he said, “Son, why didn’t you use all the   50  that you had? The boy replied with tears, “But I did, Daddy, I did! I   51  all that I had!” “No, son, you didn’t,”  52  the father kindly. “You didn’t   53  me to help you.” With that the father picked up the rock and   54  it out of the sandbox.

Are you discovering that you don’t have the strength to move your “rocks” away? There is ONE who is always willing to   55  you with the strength you need. We also need that strength, especially in our daily life.

1.                A．hid            B．left            C．put  D．discovered

2.                A．walked         B．jumped         C．traveled  D．dug

3.                A．courage        B．pride           C．effort    D．pleasure

4.                A．however        B．still            C．thus D．even

5.                A．put            B．raise           C．take D．break

6.                A．large           B．difficult         C．hard D．much

7.                A．decided        B．refused         C．agreed   D．planned

8.                A．inventions      B．progress        C．mistakes D．changes

9.                A．tried           B．failed          C．thought   D．started

10.               A．success        B．goal           C．result D．wish

11.               A．Gradually       B．lately          C．Properly   D．Finally

12.               A．watched        B．helped         C．followed   D．taught

13.               A．loud           B．happy          C．sweet D．strict

14.               A．Angrily         B．Movingly       C．Suddenly  D．Gently

15.               A．knowledge      B．strength        C．tools  D．ability

16.               A．wasted         B．brought        C．used  D．carried

17.               A．replied         B．corrected       C．shouted   D．praised

18.               A．advise         B．force          C．ask   D．want

19.               A．collected       B．threw          C．chose D．broke

20.               A．provide        B．lend           C．show D．pass

A breathtaking trick potentially left over from our ancestors might be found in us — the ability to sense oxygen through our skin.

Amphibians, animals such as frogs that can live both on land and in water, have long been known to be capable of breathing through their skin. In fact, the first known lungless frog that breathes only through its skin was discovered recently in the rivers of Borneo.

Now the same oxygen sensors found in frog skins and in the lungs of mammals (哺乳动物) have unexpectedly been discovered in the skin of mice.

“No one had ever looked,” explained Randall Johnson, a biologist researcher.

Mice and frogs are quite distant relatives, so the fact they have these molecules (分子) in common in their skin suggests they might well be found in the skin of other mammals, such as humans.

“We have no reason to think that they are not in the skin of people too,” Johnson said.

These molecules not only detect oxygen, but help increase levels of vital red blood cells, which carry oxygen around the body. Normal mice breathing in air that is 10 percent oxygen—a dangerously low level similar to conditions at the top of Mount Everest, and about half that of air at sea level. However, mice that had the oxygen sensor HIF-1a genetically removed from their skin failed to produce this hormone (荷尔蒙) even after hours of such low oxygen.

These findings, if they hold true in humans, suggest one could raise the level of oxygen circulating inside the body. This could help treat lung diseases and disorders such as anemia (贫血症) without injecting drugs, which make up a multibillion-dollar market, Johnson said.

Athletes also often try to get more oxygen delivered to their muscles in order to improve their performance. They often do this by training at high altitudes or in low-oxygen tents. The new study suggests they might want to expose their skin as well as breathing in low-oxygen air to improve their performance. “It’s hard to say what exactly might be done, however—there’s a lot we don’t know yet,” Johnson explained.

The scientists detailed their findings in the April 18 issue of the journal Cell.

1.Which of the following statements is TRUE according to the passage?

A．It has long been expected oxygen sensors exist in mice’s skin.

B．People have to surf the Internet to read detailed findings.

C．It has been proved that these findings help treat lung diseases.

D．Johnson believes that Oxygen sensors also exist in human skin.

2.One of the functions of the molecules mentioned above is _______.

A． increasing level of oxygen                B．improving athletes’ performance

C．detecting oxygen                       D．carrying oxygen around the body

3.What is Johnson’s attitude to the application of the findings to the athletes’ training?

A． Hesitating        B．Doubting          C．Positive           D．Negative

4.The best title of the passage may be _______.

A． Humans Might Sense Oxygen Through Skin

B．Frogs And Mice Are Distant Relatives

C．First Known Animal Breathes Through Skin

D．Great Findings Benefits Athletes A Lot