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All across California, honeybees are flying away from their hives(蜂箱) and dying. Empty hives are causing a lot of worry about some important food crops.
Bees give us a lot more than delicious honey. They are pollinators(授粉者)—they enable plants to produce the fruits and nuts we enjoy by carrying pollen from one plant or flower to the next. The wind pollinates oats, corn, and wheat, but many other plants (like apple and cherry trees and melon vines) depend on insects, bats, and birds. In the U.S., millions and millions of bees kept by human beekeepers fly around doing a lot of this important work for food crops. “Bees are worth protecting because their work adds so much to our diet,” says Dr. Jeff Pettis of the Bee Research Laboratory.
California’s almond (杏仁) crop alone depends on about half the bees in the country. But now the almond crop and many others could be in trouble with so many bees dying.
Researchers at government and university labs all over the country are trying to figure out why so many bees are dying. However, bees are hard to study. Most die away from the hive, so researchers don’t have dead bodies to examine. And when researchers return to a hive after two weeks, about half the bees they studied on their first visit will be dead, replaced by new ones in the natural life cycle of bees. “It isn’t like studying a large animal like a cow that doesn’t move around much and is easy to find out in the cow field,” says Pettis.
Researchers have some ideas about what could be affecting bee health. They could be sick from poisons widely used to kill insects, or they might not be getting enough good food to stay strong. Also, tiny insects called mites feed on bees. “A virus or bacteria could also be doing the killing.” explains Pettis.
1.What is Paragraph 2 mainly about?
A. The wind helps pollinate.
B. Bees are important in food crops.
C. Bees give us a lot of delicious honey.
D. Cherry trees are pollinated by bees.
2.Bees are hard to study because ____________.
A. they move around too much
B. new bees soon replace all the bees studied by researchers
C. they are too tiny
D. they never return to hives
3.What could cause so many bees to die?
A. Poisons to kill birds. B. Eating too much.
C. Large insects. D. Some virus.
4.What can we learn from the article?
A. A large number of bees have died in the hive.
B. Without bees, some foods would disappear from our diet.
C. Only researchers in California want to know what kills bees.
D. Large animals are easier to study than tiny insects.
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根据下列各句句意及所给单词的首字母或汉语提示,用正确形式的单词填空。并把完整单词填写在答题卷相应的位置上。
1.The old woman c_______ to the police about the noise downstairs, which prevented her from sleeping at night.
2.Terrorists planned to make the two planes c_______ in the U.S.A. but failed.
3.He won the match and I went over to give him my sincere c__________.
4.It is generally accepted that the dove (鸽子) is the s_______ of peace.
5.Scientists have to do lots of s_______ researches before they draw a conclusion.
6.The video, which _______ (结合) singing and dancing, is popular with students.
7.In the summer holiday, I will visit some _______ (历史的) sites in Nanjing.
8._______ (幸运的是), there are still five minutes left before the class.
9.The Mid-Autumn Festival is a special _______ (场合) for family.
10.On an _______ (极端地) cold night, the poor girl froze to death on the street.
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Bill Clinton was born on Aug.19,1946.Three months before his birth,his father had died when driving home to his pregnant wife,Virginia,he went off a high way,was thrown from the car and drowned in a river.
When Bill was 4,his mother remarried Roger Clinton.And there were always troubles:a sometimes voilent,alcoholic stepfather and a half-brother.Only one year after the marriage,the drunken stepfather fired a shotgun at the ceiling to keep his bride and stepson from leaving the house.Virginia was very much frightened.So Roger Clinton beat Virginia from time to time.But teenager Clinton played a role of protector of his mother bravely.The stepfater never laid another band on Virginia.
In high school,he was very good at Latin and maths.He also played saxophone in the hand.At age 16,as a member of a youth group,Clinton met President John F.Kennedy at the White House,it led him to the life of public service.Once he set his mind to do something,he did not give up.He was elected governor of Arkansas at the age of 32.
Clinton has said he ran for president to make the country a better place for people like Chelsea,his daughter.He did win.At the age of 46,he became the third youngest president in the nation's history.
When this passage was published,Clinton was_________.
A.governor of Arkansas B.a famous professor
C.President of U.S.A. D.President of a university
Clinton's own father died_________.
A.before Clinton was born
B.after Clinton was born
C.from drinking too much brandy
D.when Clinton's mother was giving birth
Clinton protected his mother by_________.
A.fighting against his stepfather
B.beating his stepfather
C.having long talks with his stepfather
D.the means we don't know
The word “it” in “It led him to the life of public service”refers to_________.
A.Clinton's high school education
B.becoming a member of a youth group
C.Clinton's visiting President Kennedy
D.doing public service
查看习题详情和答案>>When the TV viewer turns on his set, what sort of programs does he have to choose from? You might think there would be more programs devoted to entertainment than to anything else, but that’s not the case. In most countries, fewer than 20% of broadcasting hours are devoted to entertainment. U.S. figures are high----34.8% , and the unloving Canadians are even higher with 44%. Except Canada and Italy, all countries give more broadcasting time to education than to either information (news , documentaries and so on) or entertainment programs. Of course, few educational broadcasts take place during peak viewing times. In Japan though , more than 60%of broadcasting time is taken up with education of one kind of anther----just another example of the businesslike Japanese philosophy. In the U.K., the figure is 56.4% . the Italians have fewer educational programs than anyone else. They don’t go in for entertainment either. Only about ten percent of viewing time is devoted to dramas and serials, quiz shows, music, sports etc. You will find more news information programs on Italian TV than anything else. That’s understandable in a country experiencing social and political changes. Italians rely on TV to tell them what’s going on---and events are happening almost too fast to follow. The percentage of time the U.S. devoted to news and documentary programs is much smaller. After education, most TV time is given to entertainment. Many of these programs are shown around the world.
1.Based on this passage, the greatest percentage of TV broadcasting hours to educational is in __.
A.Japan |
B.Italy |
C.Canada |
D.the United States |
2.More news information programs are broadcast on Italian TV than anywhere else because the Italians ___.
A.are interested in what is happening in the world. |
B.Like to follow the changes that are going on in their social life |
C.Prefer to learn news information on TV rather than in newspapers |
D.Expect TV to tell them the latest news about what is going on in their country |
3. So far as the broadcasting hours devoted to entertainment , which of the following is true?
A.The Japanese figure is the highest in the world. |
B.The U.S. figure is smaller than the U. K. figure |
C.The U.K. figure is second to the Japanese figure |
D.The Canadian figure is higher than that of any other country. |
4.In the United States, ____.
A.TV programs are shown for world audience to watch |
B.Most of TV broadcasting hours are give to entertainment |
C.Educational programs are shown during peak viewing times |
D.TV broadcasting hours devoted to education are more than those devoted to entertainment |
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The basic flag of the United States is one of the world's oldest national flags.Only the basic flags of Austria,.Denmark, Great Britain, the Netherlands, Sweden, and Switzerland are older.
During the discovery and settlement of what is now the United States, the flags of various European nations were flown over the land, as symbols of possession.Later, in the Colonial and Revolutionary War periods, flags representing famous persons, places, and events were flown in the American Colonies.
The first official flag of the United States was created by Congress on June 14, 1777.It consisted of 13 alternate red and white stripes? and 13 white stars in a field of blue, representing the 13colonies that had declared their independence in 1776.Congress adopted a new flag of 15 stars and 15 stripes in 1795, to give representation to the two new states admitted into the Union, Vermont and Kentucky.
By 1817 there were 20 states in the Union, and it became apparent that adding one stripe for each new state would destroy the shape of the flag.As a result.Congress in 1818 restored the original design of 13 stripes and provided that each state was to be represented by one star.In 1921 Preside William H.Taft made the first official provision for the arrangement of the stars.He ordered that there be six even rows of eight stars each.Previously the arrangement of the stars had
been left to the flag- maker's fancy.
The evolution of the stars and stripes reflects the growth of the United States.After the admission of Hawaii into the Union in 1959, the flag was officially changed for the 26th time since its creation.
There are many government flags flown in the United States in addition to the national flag.Among them are the president's and vice-president's flags and those of the federal epartments and some federal agencies.Each state in the Union has an official flag.The United States Navy uses special flags for signaling.
1.The basic flag of the United States is _____.
A.the oldest national flag in the world
B.one of the world's oldest flags
C.the most beautiful flag in the West
D.as old as the basic flags of some European nations
2.Before the War of Independence the flags of various European nations flown over the land were symbols of .
A.self- rule B.occupation
C.peace and friendship D.independence
3.The first official flag of the United States was adopted _____.
A.before the Independence War
B.right after the Independence War
C.when independence was declared in 1776
D.during the War of Independence which ended in 1783
4.The 13 red and white stripes and13 white Stars represent____.
A.13 independent states
B.the colonies that declared independence in 1776.
C.the U.S.Congress
D.13 famous figures in the American colonies
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