閱讀理解。
     Have you ever noticed the colour of the water in a river or stream after a heavy rainfall? What do
you think caused this change in colour? It is soil that has been washed into the river from the riverbank
or from the nearby fields.
     Components of Soil
     Soil is made up of a number of layers (層), each having its own distinctive colour and texture. The
upper layer is known as the litter. It acts like a blanket, limiting temperature changes and reducing water
loss. The topsoil layer is made up of small particles of rock mixed with rotten plant and animal matter
called humus (腐殖質(zhì)), which is black and gives the topsoil its dark colour. This layer is usually rich in
nutrients, oxygen, and water. Below the topsoil is the subsoil, a layer that contains more stones mixed
with only small amounts of organic matter. This layer is lighter in colour because of the lack of humus.
Beneath the soil lies a layer of bedrock.
     Soil forms from the bottom up. Over time bedrock is attacked by rain, wind, frost, and snow. It is
gradually broken down into smaller particles in a process called weathering. Plants begin to grow, and
rotten materials enrich the topsoil. Most of the soil in Eastern Canada, for example, was formed from
weathered rock that was exposed when the ice disappeared l2,000 years ago.
     Water Beneath the Soil
     Surface water collects and flows above the ground in lakes, ponds and rivers. Once in the soil or rock,
it is called groundwater. Gravity pulls groundwater through the soil in a process called percolation (滲透).
Eventually the water reaches a layer called the water table. Under this is bedrock through which water
cannot percolate.
     As water percolates downward, it dissolves organic matter and minerals from the soil and carries them
to deeper layers. This causes a serious problem because plants require these nutrients for growth.
     Soil pH
     Soil can be acidic neutral or basic. The pH of the soil is determined by the nature of the rock from
which it was formed and by the nature of the plants that grow and rot in it.
     The acidity of rain and snow can lower the pH of the groundwater that enters the soil. By burning fossil
fuels such as coal,oil and gasoline, humans have been contributing to higher levels of acidity in many soils.
When fossil fuels are burned, gases are released into the air and then fall back to earth as acid rain. Acid soil
increase the problem of carrying nutrients to lower soil levels. As nutrients are removed, soil is less fertile.
Plants grow more slowly in acidic soil, and also become easily attacked by diseases.
1. The layer of soil that provides necessary nutrients for plant growth is called _____.
A. 1itter
B. topsoil
C. humus
D. subsoil
2. According to the text, which of the following is NOT true?
A. Soil forms from weathered rock on the earth surface.
B. The deeper layer of soil is darker in colour than the surface soil.
C. Air pollution is partially responsible for acid soil.
D. Groundwater tends to carry away nutrients for plant growth.
3. We can infer from the passage that the water table lies _____.
A. between the topsoil layer and the subsoil layer
B. in the subsoil layer above bedrock
C. between the subsoil layer and bedrock
D. in the bedrock layer beneath the subsoil
4. The underlined word "dissolve" is used to express the idea that organic matter and minerals from soil
    are _____.
A. rushed away into the river
B. cleaned and purified by water
C. destroyed and carried away by water
D. mixed with water and become part of it
練習(xí)冊(cè)系列答案
相關(guān)習(xí)題

科目：高中英語(yǔ) 來(lái)源：黃岡重點(diǎn)作業(yè)　高三英語(yǔ)（下） 題型：050

閱讀理解

　　“Let's go down one more , push your enter key…” says a young man helping senior citizens work a web site on the Internet.

　　David Lansdale has found a way to light up the lives of the elder. He gets them wired to the Internet. “If you hit your enter key , it will bring up this particular e-mail….”

　　Pauline Allen is one of those who have started using the Internet. “I thought I was through with life; I was ready for a rocking chair, because I was 86 years old. And I haven't found the rocking chair yet. ” “You found the key-board?” asks the reporter. “That's right, I found the key-board.”

　　The average age of Lansdale's students is around 68. All are in nursing or assisted care homes. He used family relationships to introduce them to the World Wide Web.

　　David Lansdale says, “Here they are in California; the family are in New York. The chance to connect, to cross the time and space, is very good chance to them. ”

　　“I hear you are so beautiful. ” Lillian Shier writes an e-mail to a newborn great granddaughter. Working with one another, the seniors learn as a group. They learn to master the Internet and to overcome what Lansdale calls the maladies of the institutionalized: loneliness , helplessness , and loss of memory.

　　Mary Harvey says, “Bingo just doesn't interest me. But this does, believe me, this does. ”

　　Ninety-four-year-old Ruth Hyman is a star pupil and instructor. She says , “When I send a letter to my grandchildren , and great granddaughter , they hang it up in their offices , just as I used to hang their drawings on my refrigerator. Ha, ha!”

　　David Lansdale says , “There's a collective benefit （得益） . There is a way of treatment. Remember we started as a support group. ”

　　Dixon Moorehouse says , “I just wish I were 15 years old and getting to learn all this. ” The seniors call their weekly meeting Monday Night Live. And many say the meetings have given them new life.

　　Ruth Hyman says , “Three years ago , they told me I wasn't going to live. But I showed them , and got work, and I've worked ever since. ”

1．The purpose of David Lansdale's work is to ________.

[　　]

A．popularize the use of computers among the seniors

B．help the seniors connect with their families

C．organize the seniors as a group to work

D．keep the health of the mind of the seniors

2．The phrase “the maladies of the institutionalized ” in the sixth paragraph means “________”.

[　　]

A．the difficulties in learning

B．the problems of the old

C．the treatments of the old

D．the worries about getting old

3．How many examples does the writer give to prove the seniors enjoy the Internet?

[　　]

A．Four.
B．Five.
C．Six.
D．Seven.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：重慶市期末題 題型：閱讀理解

閱讀理解。
     Three young ladies were receiving trains to be qualified detectives (偵探) by a policeman. To test their
skills in recognizing a suspect (嫌疑人), the policeman showed the first lady a picture for five seconds and then asked how she could recognize him. She thought it easy, for the suspect had only one eye. The policeman felt disappointed at this funny answer. He showed the second lady the picture for five seconds and asked her how she would recognize him. The second girl smiled, flipped her hair, and said, "Ha! It's easy to
find the one-eared person!" Her answer also made the policeman angry. Turning to the third lady, he asked, "How would you recognize him?" He added quickly, "Think hard before giving a stupid answer. " The
third lady looked at the picture carefully for a moment and said, "HMMMM . . . he is wearing contact
 lenses (隱形眼鏡)." The policeman was surprised and speechless, because he really didn't know himself
if the man wore contacts or not. "Well, that is a good answer. Wait here for a few minutes while I check
his file. He left the room and went to his office, checked the suspect's file in his computer and returned
with a beaming smile. "Wow! I can't believe it . . . it's TRUE! The man does in fact wear contact lenses.
Good work! How were you able to make such a wise observation?" "That's easy," the girl replied, "He
can't wear glasses because he only has one eye and one ear!"
1. Which of the following cannot be concluded from the passage that detectives should have?
A. They must be humorous. 
B. They must have a strong ability of observation.. 
C. They must be good at memorizing. 
D. They must be good at thinking.
2. How did the third lady know the suspect was wearing contact lenses?
A. She sold contact lenses before.
B. She just had the same idea as the first two girls
C. She had been wearing contact lenses for a long time.
D. She wouldn't want to give the stupid answer.
3. According to the passage we can infer that ________.  
A. the suspect was easy to be recognized
B. the suspect was caught by the policeman
C. the suspect must be a disabled person
D. the picture was just a side of the suspect.
4. What will probably happen to the three ladies after this test? 
A. All of them may be given more training courses or fired.  
B. The second lady may be accepted as a detective at once.
C. The third lady is good at thinking and doesn't need any training. 
D. The first lady may be accepted as a detective at once.

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：0113 期中題 題型：閱讀理解

閱讀理解。
     An unemployed man is desperate to support his family. His wife watches TV all day and his three teenage
kids have dropped out of high school to hang around with the local toughs. He applies for a cleaner's job at a
large firm and easily passes an aptitude test. The human resources manager tells him,"You will be hired at
minimum wage, $5.15 an hour. Let me have your e-mail address so that we can contact you easily. Our
system will automatically e-mail you all the forms and advise you when to start and where to report on your
first day." Greatly surprised, the man said that he has neither a computer nor an e-mail address. To this, the
manager replies,"You must understand that to a company like ours that means you virtually do not exist.
Without an e-mail address you can hardly expect to be employed by a high tech firm. Good day."
      Unable to believe what he hears, the man leaves. Not knowing where to turn and having $10 in his wallet,
he walks past a farmers' market and sees a stand selling beautiful tomatoes. He buys a crate (柳條箱), carries
it to a busy corner and displays the tomatoes. In less than two hours he sells all the tomatoes and makes 100%
profit. From that day on, he repeats the tomato business and becomes increasingly successful as time goes on.
By the end of the fifth year he owns a fleet of nice trucks and a warehouse. The tomato company has put
hundreds of homeless and jobless people to work and the business grossed a million dollars.
     Planning for the future, he decides to buy some life insurance. The insurance adviser asks him for his
e-mail address in order to send the final documents electronically. When the man replies that he doesn't have
time to mess with a computer and has no e-mail address, the insurance salesman is surprised," No computer?
No Internet? Just think where you would be if you'd had all of that five years ago!" "Ha! If I'd had all of that
five years ago, I would be sweeping floors at Microsoft and making $5.15 an hour!" the man replies.
1. The man's kids drop out of school because ____.
A. they want to hang around with the local toughs
B. their mother watches TV all day
C. their father is only a cleaner
D. their family is very poor
2. The man applies for a cleaner's job ____.
A. but he can't accept it because the pay is too low
B. and he gets it though the pay is only $5.15 an hour
C. but he is turned down because he doesn't have an e-mail address
D. but he misses the chance because they fail to contact him
3. The man's tomatoes sell well because ____.
A. the tomatoes look very beautiful
B. he has chosen the right place to sell them
C. many jobless people help him
D. the tomatoes are contained in beautiful crates
4. From the conversation between the man and the insurance salesman in the last paragraph we
    can infer that ____.
A. the man will buy a computer soon
B. it's very easy to do tomato business
C. one does not necessarily have an e-mail address to be successful
D. the man is not able to buy any life insurance without an e-mail address

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：湖南省高考真題 題型：閱讀理解

閱讀理解。
     We were on tour a few summers ago, driving through Chicago, when right outside of the city, we got
pulled over. A middle-aged policeman came up to the car and was really being troublesome at first. Lecturing
us, he said,"You were speeding. Where are you going in such a hurry?" Our guitarist, Tim, told him that we
were on our way to Wisconsin to play a show. His way towards us totally changed. He asked, "Oh, so you
boys are in a band (樂(lè)隊(duì))?" We told him that we were. He then asked all the usual broad questions about the
type of music we played, and how long we had been at it. Suddenly, he stopped and said, "Tim, you want to
get out of this ticket, don't you?" Tim said, "Yes." So the officer asked him to step out of the car. The rest
of us, inside the car, didn't know what to think as we watched the policeman talk to Tim. Next thing we
knew, the policeman was putting Tim in the back of the police car he had parked in front of us. With that, he
threw the car into reverse (倒車(chē)), stopping a few feet in back of our car. Now we suddenly felt frightened.
We didn't know if we were all going to prison, or if the policeman was going to sell Tim on the black market
or something. All of a sudden, the pollen's voice came over in a loudspeaker. He said, "Ladies and gentlemen,
for the first time ever, we have Tim here singing on Route 90." Turns out, the policeman had told Tim that
the only way he was getting out of the ticket was if he sang part of one of our songs over the loudspeaker in
the police car. Seconds later, Tim started screaming into the receiver. The policeman enjoyed the performance,
and sent us on our way without a ticket.
1. The policeman stopped the boys to _____.
A. put them into prison
B. give them a ticket
C. enjoy their performance
D. ask some band questions
2. The policeman became friendly to the boys when ha knew they ______.
 A. had long been at the band
B. played the music he loved
C. were driving for a show
D. promised into a performance
3. The boys probably felt ______ when they drove off.
A. joyful
B. calm
C. nervous
D. frightened

查看答案和解析>>

科目：高中英語(yǔ) 來(lái)源：湖南省高考真題 題型：閱讀理解

閱讀理解。
     Collections were the inspiration (靈感) for a project at Thomas Tallis School, which formed part of the
Imagine Children's Literature Festival last autumn. Each child (aged 12-13) beatified a box and wrote a story
on the subject of collections to throw inside it. The boxes were spread within the Royal Festival Hall's
Ballroom. Some were left empty to encourage
     The subject chosen by Luren was an imaginative one. "It's a sort o f Cinderella (灰姑娘) story," she told
me, inspired by a collection of letters from her cousin, ha the story these become love letters, burned by a
creel stepmother. Lauren's best friend Charlotte is the stepmother. "I'm in Charlotte's story too," says Lauren,
"and I get run over." Charlotte's tale was inspired by the girls' coin collection."We've collected foreign coins
for years-since our families went on holiday to Tenerife." she explains."That was before the Euro, so we put
pesetas in." Lauren continues: "I fred a coin in the road, go to get it and get run over. I'm in hospital and then
I die." Charlotte adds: "Or she might not die. I haven't decided yet."
     Millie Murray, who is a tea-novel author, thinks that setting the subject of collections was a useful
inspiration to their creativity rather than a restriction (限制). "In the beginning I thought, 'Will the children be
able to do it?'" she says. "But it's been fruitful. Some have their own collection, some have parents who do,
and some have wlstten complete stories. It's made them think about something they wouldn't have otherwise,
winch can only be a good thing."
1. What were the children asked to do in the project?
A. To meet friends at Thomas Tallis School
B. To write stories on the subject of collections.
C. To encourage visitors to write their own stories.
D. To have their friends for characters in the stories.
2. The underlined word "pesetas" in Paragraph 2 is a kind of _____.
A. story
B. collection
C. inspiration
D. foreign coin
3. From the stories by Lauren and Charlotte, we know that _____.
A. Charlotte hurt herself when getting a coin
B. both of them developed their imagination
C. both of tram will die in each other's stories
D. Latwen's cousin posted her some love letters
4. Millie Murray thinks ______.
A. collections could inspire writing creativity
B. it was good for parents to have collections
C. inspirations were very useful in writing stories
D. setting collection subjects restricted inspirations

查看答案和解析>>

同步練習(xí)冊(cè)答案