Earthquakes and volcanic eruptions usually cause the largest, most disastrous debris(碎石)flows．A great many victims of the earthquake that struck Wenchuan of Sichuan Province were killed not by the quake itself but by the sudden large amounts of debris that followed．
Most debris flows occur where the soil is composed mainly of sand or colluviums(崩积层)．Loose soils made up of bits of sand or colluviums fall apart easily and are main material for fast-moving debris flows．
Scientists have conducted endless experiments to find out how debris flows work．They have learned that the amount and the timing of water entering the soil are crucial(决定性的)．Typically, that means debris flows often occur when a long rainy period of many weeks is followed by an intense, brief heavy rain．
More often than not, however, debris flows are started by water, in the form of rain, snow, or river flow．In 1998, heavy rains from Hurricane Mitch unleashed about one million tons of mudslides, burying thousands of people, in Central America．
Water flows through the soil until it hits a hard layer of bedrock or clay．There the water builds up, filling the tiny spaces between the soil and rock．That buildup reduces the natural friction(摩擦力)that keeps the rock and soil debris lying on the slope．If conditions are approaching dangerous levels, the slope will then fall down．
Despite what scientists know about the fact, debris flows are still impossible to predict at present because there are many other uncertainties affect the stability of each slope．However, one thing is known：On hillsides where one debris flow has occurred, another will eventually follow．The next debris flow could take days, weeks, or years to happen．
(1)
The passage is mainly about ________．
[ ]
A．
when and where debris flows occur
B．
the experiments that scientists conduct
C．
the causes of debris flows
D．
the possible ways to predict landslides
(2)
Debris flows usually take place ________．
[ ]
A．
during earthquakes and volcanic eruptions
B．
after a heavy rain or an intense snowstorm
C．
when there is a right amount of water entering the soil
D．
when a long rainy period is followed by a heavy rain
(3)
The underlined word "unleashed" in the 4th paragraph most probably means "________"．
[ ]
A．
released
B．
organized
C．
provided
D．
invented
(4)
We can infer from the text that
[ ]
A．
water can flow through a hard layer of bedrock or clay
B．
the friction can keep the rock and soil debris flowing
Our town is in the eastern part of our country．Once a year, we elect a girl to show how beautiful and great our town is．All the girls are eager to get this position in an effort to become popular．
It was not an easy choice this year, since there were eight girls to choose from．The elder judge finally decided that either Sara or May would get the position．Both girls were beautiful with extraordinary appearance．Besides, they had good education and cared about how pollution had a bad effect on the earth．Most important, both girls got up early to eat eggs at their breakfast．Eggs were important to people of the east because our economy depended mainly on the production of eggs．
“Either girl will win, ”my father said．“But someone will cry in the end．”
“Either will be fine,” I said．“They are both great girls．”
The final round was held at east edge of our town．Sara lived nearby, so she did not need to get up early to arrive．However, she was the first person there．“You know what they say about the early bird．” she said with a smile．
However May arrived fifteen minutes late to the competition．“It’s the taxi driver’s fault,” she said．“I told him to head east, but he was in one ear and thought I said Bread Cheese．” You know, Bread Cheese was the name of our neighboring town．
I thought May would certainly lose because she was late, but to my surprise, she turned out to be this year’s winner．The judge liked her answer to the last question．“If you could have anything in the world, what would it be?” Sara had replied, “World peace．” May, on the other hand, said, “Better market to have our eggs sell well．”
(1)
Why was it difficult to make a choice this year?
[ ]
A．
The girls just looked alike．
B．
People had to choose from eight girls．
C．
All the girls wanted to get the position．
D．
The judges couldn’t agree with each other．
(2)
In the passage the underlined sentence “You know what they say about the early bird．” means ________．
[ ]
A．
she liked the early bird very much
B．
she was sure that she would succeed
C．
she lived nearby, so she should get there early
D．
she wanted to show off her good language knowledge
(3)
Why was May chosen in the end?
[ ]
A．
Because her answer was cleverer and exact．
B．
Because she gave a different answer from Sara’s．
C．
Because she looked more beautiful than the other girl．
D．
Because her answer was more practical than that of the other girl．
(4)
According to the passage, which of the following maps is correct?( )
阅读理解
Your cellphone holds secrets about you．Besides the names and numbers that you’ve programmed into it, traces of your DNA remain on it, according to a new study．
DNA is genetic material that appears in every cell．Like your fingerprint, your DNA is unique to you－unless you have an identical twin．Scientists today usually analyze DNA in blood, saliva(唾液)or hair left behind at the scene of a crime．The results often help detectives identify criminals and victims．
Meghan J．McFadden, a biologist at McMaster University in Hamilton, Ontario, heard about a crime in which the suspect bled onto a cellphone and later dropped it．This made her wonder whether traces of DNA remained on cellphones－even when no blood was involved．To find out, she and a colleague collected flip-style(翻盖式)phones from 10 volunteers．They collected invisible traces of the users from two parts of the phone：the outside, where the user holds it, and the speaker, which is placed at the user’s ear．
The scientists cleaned the phones using a liquid mixture made mostly of alcohol．The aim of washing was to remove all detectable traces of DNA．The owners got their phones back for another week．Then they returned the phones and the researchers collected traces on each phone once more．They discovered DNA that belonged to the phone’s owner on each of the phones．
Surprisingly, DNA was even picked up immediately after the phones were cleaned．That suggests that washing won’t remove all traces of evidence from a criminal’s cellphone．So cellphones can be added to the list of clues that can settle a crime-scene investigation．
(1)
In a crime-scene investigation, now experts are likely to turn to ________．
[ ]
A．
the criminal’s fingerprint
B．
the DNA analysis of physical items
C．
the detectives
D．
the criminal’s cellphone
(2)
According to the passage, McFadden was inspired by ________．
[ ]
A．
the secrets stored in people’s cellphones
B．
the special characters of DNA
C．
a cellphone-involved case
D．
the challenging job of detectives
(3)
According to the passage, the potential application of the new study would be ________．
[ ]
A．
identifying criminals
B．
designing new cellphones
C．
protecting individual privacy
D．
preventing cellphone-involved crimes
(4)
Which of the following has the closest meaning with the underlined word“identify”in Paragraph 2?
[ ]
A．
imagine
B．
recognize
C．
discover
D．
determine
阅读理解
Many years ago, there was a story of a school teacher－Mrs.Thompson．She told the children on the first day that she loved them all the same．But that was a lie．There in the front row was a little boy named Teddy Stoddard．He didn't play well with the other children and he always needed a bath．She did not like him．
Then Mrs.Thompson got to know that Teddy was actually a very good boy before the death of his mother．Mrs.Thompson was ashamed of herself．She felt even worse when, like all her other students, Teddy brought her a Christmas present too．It was his mother's perfume．
Teddy said,“Mrs.Thompson, today you smell just like my Mom used to．”After the children left she cried for at least an hour．On that very day, she stopped teaching reading, writing and maths．Instead, she began to teach children．
Mrs.Thompson paid particular attention to Teddy．The boy's mind seemed to come alive．The more she encouraged him, the faster he improved．By the end of the sixth grade, Teddy had become one of the smartest children in the class．
Six years went by before she got a note from Teddy．He wrote that he had finished high school, third in his class, and she was still the best teacher he ever had in his whole life．He went to college．Mrs.Thompson got two more letters from him with the last one signed, Theodore F.Stoddard, M.D.(医学博士)．
The story doesn't end there．On his wedding day, Dr．Stoddard whispered in Mrs.Thompson's ear,“Thank you, Mrs.Thompson, for believing in me．You made me feel important and showed me that I could make a difference．”
Mrs.Thompson, with tears in her eyes, whispered back,“Teddy, you have it all wrong．You were the one who taught me that I could make a difference．I didn't know how to teach until I met you．"
(1)
According to the first paragraph, which is true between Teddy and his teacher?
[ ]
A．
Mrs.Thompson loved him all the same．
B．
Mrs.Thompson didn't play well with him．
C．
Mrs.Thompson told Teddy not to tell a lie．
D．
Mrs.Thompson had a dislike of Teddy
(2)
From the passage, we can infer that ________．
[ ]
A．
Teddy loved his mother very much
B．
Mrs.Thompson told a lie and felt ashamed
C．
Mrs.Thompson cried because she misunderstood Teddy
D．
Teddy hoped Mrs.Thompson could treat him like his mom
(3)
Why did Teddy become one of the smartest children in the class?
[ ]
A．
Mrs.Thompson paid little attention to him．
B．
Mrs.Thompson gave him encouragement more often
C．
Teddy was clever and worked hard．
D．
Teddy got well on with other students．
(4)
As a teacher, Mrs.Thompson realized that it was important ________．
