The shocking disappearance of Malaysia Airlines Flight MH370 has captured the attention of millions around the world as the search for the airplane and its passengers and crew continues. What happened to the flight’s 239 passengers and crew after the plane left Kuala Lumpur on Saturday? It is becoming an increasingly desperate question as the days pass.
But it’s hardly the first mystery of its kind. Here are some half-solved and unsolved airline mysteries that kept investigators clueless for years.
Air France Flight 447: An Airbus A330 flight from Rio de Janeiro to Paris plunged into the Atlantic Ocean in 2009, killing all 228 passengers and crew on board. But it took a full five days for search and rescue teams to find the wreck（残骸）and another three years for investigators to report that ice crystals had caused the autopilot (自动驾驶仪) to disconnect. The bodies of 74 passengers remain unrecovered.
Amelia Earhart: Ace (王牌) pilot Amelia Earhart disappeared in her twin-engine monoplane Electra over the Pacific Ocean in 1937 in an attempt to circumnavigate the globe. No trace of her plane was ever found even after a multi-million dollar search effort, and Earhart was officially declared dead in 1939.
Flying Tiger Line Flight 739: A U.S. military flight left Guam in 1962 with more 90 personnel headed for the Philippines, but it never arrived. The pilots never issued a distress call, and 1,300 people involved in the U.S. military search never found any trace of wreckage.
British South American Airways: It took more than 50 years to find any trace of the 11 people aboard a 1947 flight that disappeared in the Andes Mountains. A pair of Argentineans rock climbers discovered engine wreckage in the Andes in 1998, and an army expedition later found human remains as well.
Uruguayan Air Force Flight 571: A flight headed to Santiago, Chile carrying 45 passengers and crew crashed into the Andes Mountains in poor weather in 1972, killing twelve people. In the meantime, eight were killed in an avalanche (雪崩) that hit the plane’s wreckage where they were taking shelter, and the rest stayed alive by eating the flesh of the dead before they were finally found more than two months after disappearing out of the sky.The underlined word “plunged” in Paragraph 3 is closest in meaning to _____.
| A．jumped | B．broke |
| C．flew | D．dived |
What can we learn from Uruguayan Air Force Flight 571? _____.
| A．12 people were lost until now. |
| B．25 people were rescued instantly. |
| C．The rest who stayed alive killed 8 people. |
| D．8 were killed by a fall of a large mass of snow down a mountainside. |
From the passage, what could have led to British South American Airways crash? _____.
| A．The bad weather. | B．Not mentioned. |
| C．The ice crystals. | D．The lightening. |
Which of the following is TRUE according to the passage? _____.
| A．Earhart was declared dead by the authorities two years later. |
| B．The bodies of Flight 447 had all been found after three years. |
| C．Two Argentineans rock climbers discovered the dead in the Andes. |
| D．Malaysia Airlines Flight MH370 was regarded as the largest air crash. |
The passage has been written to _____.
| A．introduce the loss of Malaysia Airlines Flight MH370 |
| B．explain how to avoid airplane disappearances as a pilot |
| C．tell readers mysterious airplane disappearances in Aviation History |
| D．call on people to protect themselves |
In the early 80’s, I walked across the Burrard Bridge in Vancouver. Not alone, however. With me were more than 50,000 persons, mostly of my generation, on the Walk for Peace. Loving peace, I think, is one of three important qualities of my generation.
That desire for peace has been an important char
acteristic of my generation for a long time. I grew up in the 60’s and early 70’s. At that time, many of us took part in demonstrations（示威游行） against the Vietnam War. Many people of my generation have devoted their lives to world peace, and lately we have seen success: US and Russian nuclear weapons are half their 1980 levels and nuclear disarmament（裁减军备） is agreed upon worldwide.
Another characteristic of my generation is our participation in the “marriage revolution”. We were the first generation that had access to safe and reliable birth control. The idea of “free love” made it easier for men and women to safely express their love before marriage. The marriage revolution gave us power, especially to women, and the world was changed forever.
The most important characteristic, however, is that many of us are deeply concerned about the environment. The results of my generation’s activities can be seen everywhere.
Although not all of us have participated, it is sure that we will continue to have a large impact on North America. We are nearing 50 years old, an age where people of my generation will become successful in politics and then, who knows what changes will come.
59. Which of the following does not belong to the characteristics of the author’s generation?
A. Travelling peacefully. B. The wish for peace.
C. Belief in the idea of “free love”. D. Protecting the environment.
60. “My generation” may be people born between ________.
A. the 50s and 60sB. the 60s and 70s
C. the 70s and 80s D. the 80s and 90s
61. The passage implies that ________.
A. most of the author’s generation died for world peace
B. all the countries agreed to remove the nuclear weapons
C. the demonstrations against the Vietnam War achieved success
D. some of the author’s generation may have greater influence on the country
We learned that fossil fuels were formed before and during the time of the dinosaurs（恐龙）. We are using up the fuels. We can save fossil fuels by protecting and finding ways to use energy from “endless sources”, like the sun and the wind. Some people suggest that we should start using hydrogen（氢）.
Hydrogen is a colorless, smell-less gas that takes up 75 percent of the whole universe. Hydrogen is found on earth only in mixture with other elements such as oxygen, carbon and nitrogen. To use hydrogen, we must separate it from these other elements.
Hydrogen can be used in NASA’s space program as fuel for the spaceships, and in fuel cells that provide heat, electricity and drinking water for astronauts. Fuel cells are devices that directly change hydrogen into electricity. In the future, hydrogen could be used to fuel vehicles and aircraft and provide power for our homes and offices.
Hydrogen can be made from natural gas. An electrical current can also be used to separate water into its elements of oxygen and hydrogen. Some plants in the sea and bacteria（细菌） give off hydrogen through sunlight under certain conditions.
Hydrogen as a fuel is high in energy. Yet a machine that burns pure hydrogen produces almost zero pollution. NASA has used liquid hydrogen since the 1970s to drive rockets and spacecraft into orbit. Hydrogen fuel cells power the spacecraft’s electrical systems, producing clean by-product-pure water, which the crew drinks.
56. We can get hydrogen from the following EXCEPT ______ according to the passage.
A. natural gas B. water C. creature in the sea D. bacteria
57. Why could the hydrogen be used widely in the future?
A. Because it is of high quality.
B. Because it has no pollution.
C. Because it is easy to get it from all kinds of ways.
D. Because there are much hydrogen existing in the universe.
58. The passage mainly tells us ________.
A. the usage of a new energy source B. the future energy sources
C. a new energy source －hydrogenD. how to get the energy source
The bee，like the ant，is a social insect（昆虫）.Bees live in large groups in box-like houses called hives or beehives.Every bee does a certain job that helps the other members of th
e group.In a beehive there live three kinds of bees:the queen bee，the male bees and the worker bees.The worker bees are born to be hard-working，flying from flower to flower collecting nectar（花蜜），which is made up mostly of sugar mixed with water.Bees draw this nectar into their honey bags where some sort of liquid in their bodies turns the nectar into honey.The newly made honey flows slowly from the bees’ underside and then is stored in small cells in the hive.When the weather turns cold，and there are no flowers for them to collect nectar，the stored honey will see them through the winter months.People who raise bees and depend on bees for a living are thought of as beekeepers.A bee-keeper usually keeps hundreds of hives，and removes honey from hives and keeps it in glass bottles or jars.Honey usually appears as a clear golden-colored liquid，but this lie
s in the sort of flowers from which bees have taken the nectar.
66.The best title of this passage is_______.
A.The Social Habits of Bees B.Three Kinds of Bees
C.The Production of Honey D.Bee Keepers’ Work
67.Bees are regarded as social insects because they_______.
A.form themselves into a good organization
B.have learned something from human society
C.need beekeepers to arrange their jobs
D.are born to work hard
68.The color of honey in its final stage depends on the_______.
A.type of flowers which the nectar is taken from
B.amount of sugar the beekeeper gives the bees
C.season in which the nectar is collected
D.quantity of water the bees are able to drink
69.Worker bees are always busy collecting nectar in order to_______.
A.help beekeepers to earn money from honey
B.turn it into honey
C.have something to eat in winter months
D.please the queen bee at the hive
70.During the course in which nectar change into honey_______.
A.water and sunlight are necessary conditions
B.some special liquid inside bees must be in the presence
C.many complex（复杂的）chemical changes will take place
D.worker bees have to bring up what they collected into their hive
Two scientists in California now think they can find out a person’s real age.Jeffery Bada and Patricia Masters do chemical tests on teeth.When we are born the amino acids（氨基酸）in our teeth are in one form.Then，as we grow older these amino acids change into a second form.Every year，one thousandth of the amino acids changed.So，by testing just one tooth and counting the number of amino acids in each form，Bada and Masters can work out a person’s age.They tested a tooth from the body of an Eskimo（爱斯基摩人）woman who died 1 600 years ago.From the appearance of her body，she was between 50 and 60 years old when she died.The tooth test put her age at 53.Then the Russian Government sent them a tooth from an old man in Georgia.The tooth said she was 99.Her real age was 96.The Russians are now hoping to send more teeth，from the very old people without birth certificates（出生证明书）.But there are problems.Some of the centenarians（百岁老人）have lost all their teeth.The others want to keep their teeth until they drop out naturally.So the Russian Government and the American scientists have to wait and hope.
61.Jeffery Bada and Patricia Masters believe that they can tell a person’s age according to_______.
A.an experiment on his bone
B.the shape and condition of his teeth
C.a test on the amino acids within his body
D.the changing form of amino acids in his teeth
62.According to the passage，which of the following statements is true?
A.The amino acids in an adult’s teeth may differ from those in a baby’s.
B.The number of amino acids in a 20-year-old man is different from that when he was seven.
C.Amino acids in one teeth changes without affecting their forms.
D.Scientists no
w can tell how long a person will live by testing his teeth.
63.Why are the two scientists asked to find out some very old Russians’ age?
A.Because the Government wants to know how long these old people can live.
B.Because they have no birth certificates.
C.Be
cause people who have tooth problems tend to live longer.
D.Because the Government wants to know their dates of birth and death.
64.In order to find out the exact age of some people over 100，both the Russian Government and American scientists_______.
A.should wait until all of them die
B.should pull out one of their teeth
C.have to wait for their teeth to drop out naturally
D.want to have their teeth pulled out
65.The central idea of the passage is_______.
A.the relationship between people’s teeth and ages
B.the relationship between amino acids and teeth
C.the contradiction（矛盾）between scientists and patients
D.the contradiction between the Government and the scientists
America is growing older. Fifty - eight years ago, only 4 out of every 100 people in the United States were 65 or older. To day, 10 out of every 100 Americans are over 65. The aging of the population will affect（影响）American society in many ways—education, medicine, and business. Quietly, the graying of America has made us a very different society—one in which people have a quite different idea of what kind of behavior（行为） is suitable（合适）at various , ages.
A person s age no longer tells you anything about his/her social position, marriage or health. There’s no longer a particular year in which one goes to school or goes to work or gets married or starts a family. The social clock that kept us on time and told us when to go to school, get a job, or stop working isn’t as strong as it used to be. It doesn’t surprise us to hear of a 29 - year - old university president or a 35 - year -old grandmother, or a 70 year - old man who has become a father for the first time. Public ideas are changing.
Many people say, “I am much younger than my mother— or my father— was at my age. ”No one says“Act your age” any more. We’ve stopped looking with surprise at older people who act in youthful ways.
67．It can be learnt from the text that the aging of the population in America ________ .
A. has made people feel younger
B. has changed people’s social position
C. has changed people’s understanding of age
D. has slowed down the country’s social development
68．The underlined word “one” refers to ________ .
A. a society B. America
C. a place D. population
69．“Act your age” means people should ________ .
A. be active when they are old
B. do the right thing at the right age
C. show respect for their parents young or old
D. take more physical exercise suitable to their age
70．If a 25 - year - old man becomes general manager of a big firm, the writer of the text would most probably consider it ________ .
A. normal B. wonderful
C. unbelievable D. unreasonable