题目列表(包括答案和解析)
Today we tell you about some new understanding of why cutting the main branch of a plant
or tree can lead to better development.
The findings are from researchers on two_continents.Professor Prezemyslaw Prusinkiewicz
of the University of Calgary in Canada led the research with scientists from Britain and Sweden.
Their study appears in the Proceedings of the National Academy of Sciences.
Researchers have known since the 1930s that the actively growing tip of a plant produces
a hormone(荷尔蒙)called auxin(生长素).This hormone flows down the main stem.Scientists
say the auxin has an indirect effect on buds(芽)on the side of the stem to prevent branching.
T hese buds themselves also produce auxin.The research suggests that to grow,they have
to be able to export the hormone into the main stem.But the flow from the stem tip prevents
them from doing this.The researchers wanted to find out how this blocking happens.
Professor Prusinkiewicz is on leave in Australia,but he sent us an e-mail suggesting a
simple way to understand the process.Think of a major road crowded with traffic.So many
cars are on the main road that the cars on the side roads cannot enter.
The stem is like the crowded main road.The new research shows that the buds on the
side cannot export their auxin into the main stem because it is too full.But if that main shoot
is pruned(修剪),other buds below it can start exporting.They are no longer prevented from
growing.
Ottoline Leyser from the University of York says that after a plant is pruned,all the
inhibited(被抑制的)shoot tips compete with each other to grow.In doing this,the branches
influence each other's growth.Nearby shoot tips are more likely to affect each other than those
that are far apart from each other.
Professor Leyser says the strongest branches grow best,wherever they may be on the
plant.The study found that the main shoot grows the best of all not because of its position at
the top of the plant,but mostly because it got there first.
A.Researchers have recently found out that the growing tip of a plant produces hormones.
B.Auxin has a direct effect on buds to keep branches from growing.
C.Buds on the side of the stem can’t produce hormones.
D.In order to grow,the buds on the side of the stem export the hormones into the main stem.
Why does most of the world travel on the right side today? Theories differ, but there’s no doubt that Napoleon was a major influence. The French had used the right since at least the late 18th century. Some say that before the French Revolution, noblemen drove their carriages on the left, forcing the peasants to the right. Regardless of the origin, Napoleon brought right-hand traffic to the nations he conquered, including Russia, Switzerland and Germany. Hitler, in turn, ordered right-hand traffic in Czechoslovakia and Austria in the 1930s. Nations that escaped right-hand control, like Great Britain, followed their left-hand tradition.
The U.S. has not always been a nation of right-hand rivers; earlier in its history, carriage and horse traffic traveled on the left, as it did in England. But by the late 1700s, people driving large wagons pulled by several pairs of horses began promoting a shift to the right. A driver would sit on the rear (后面的) left horse in order to wave his whip with his right hand; to see opposite traffic clearly, they traveled on the right.
One of the final moves to firmly standardize traffic directions in the U.S. occurred in the 20th century, when Henry Ford decided to mass-produce his cars with controls on the left (one reason, stated in 1908; the convenience for passengers exiting directly onto the edge, especially… if there is a lady to be considered). Once these rules were set, many countries eventually adjusted to the right-hand standard, including Canada in the 1920s, Sweden in 1967 and Burma in 1970. The U.K. and former colonies such as Australia and India are among the western world’s few remaining holdouts. Several Asian countries, including Japan, use the left as well — thought many places use both right-hand-drive and left-hand-drive cars.
【小题1】Why did people in Switzerland travel on the right?
A.They had used the right-hand since the 18th century. |
B.Rich people enjoyed driving their carriages on the right. |
C.Napoleon introduced the right-hand traffic to this country. |
D.Hitler ordered them to go to against their left-hand tradition. |
A.Austria | B.England | C.Japan | D.Australia |
A.in order to change traffic directions in the U.S. |
B.so that passengers could get off conveniently |
C.because rules at that time weren’t perfect |
D.though many countries were strongly against that |
A.Before the French Revolution, all the French people used the right. |
B.People in Britain and the U.S. travel on the same side nowadays. |
C.The Burmese began to travel on the right in 1970. |
D.All the Asian nations use the left at present. |
A.Who made the great contributions to the shift of traffic directions? |
B.How cars have become a popular means of transportation? |
C.How Henry Ford produced his cars with controls on the left? |
D.Why don’t people all drive on the same side of the road? |
五.单词拼写:(附加题:10×1.5=15分)
71.Anyone’s finger prints are u_______. There’re no same ones.
72.Most middle schools ______(禁止) students to carry cell phones to classes.
73.The opening ceremony of Beijing Olympic Games was a _____ (盛宴)for the eyes.
74. We shall o_____ difficulties to gain more achievements.
75.We must a______ (适应,调整)ourselves to new conditions.
76. It’s very cold outside .Put on your coat o______ (="or)" you will catch a cold.
77.Schooling is a _____(="lawful" 法律的) requirement for children over 5 years old in Britain and the US.
78.I s______ (发誓)that I’ll tell you everything some day.
79. His parents are 59 and 61 years old, and their a______ age is 60.
80.Changes in q______(数量) can lead to changes in quality .
One thing that British and Chinese cultures share is a love for fine tea. Today, when we think of Western tea culture, we often think of the English and beautiful china tea cups.
Afternoon tea
People believe that an English lady, Anna, first introduced the idea of afternoon tea. In the 18th and 19th centuries. the English ate only two main meals each day ,breakfast and a heavy supper that would last for several hours in the evening. As a result, people often got very hungry during the long wait between these two meals. To solve this problem, Anna came up with the clever idea of inviting some friends to join her for an afternoon meal between four and five o'clock. This meal included cakes and sandwiches. and tea was served(提供)to wash down the food. In order to make this afternoon meal important, fine china cups and plates, and silver teapots. knives, forks and spoons were used .Soon, afternoon tea parties became popular social occasions. Today, afternoon tea parties continue to play an important part in the social life in modern Britain.
Will you come for coffee?
Coffee also has an important role in British culture. People often use the words“Will you come for coffee?” to mean “Would you like to come to my home for a chat?” Normally, several different drinks such as tea, hot chocolate or a soft drink like orange Juice will be served as well as coffee. and you will be asked what you would like. However, you will not normally be offered wine at a "coffee" party.
Coffeehouses and the London Stock Exchange
In the 17th century London, coffeehouses were busy and noisy places. Businessmen and bankers went to coffeehouses to do their business, as well as to drink coffee. In fact, the London Stock Exchange(股票交易所) is believed to have started from these coffeehouses
1. Anna introduced the idea of drinking afternoon tee because she _______.
A enjoyed chatting with her friends at home
B loved fine tea and beautiful china tea cups
C. wanted to share nice food with her friends
D found people felt hungry during the long wait between the two meals
2.What does “social occasions” mean in Chinese?
A.集体婚礼 |
B.社交活动 |
C.社区表演 |
D.公共场合 |
3.f someone says to you “Will you come for coffee?”, you _______.
A.will be offered coffee only |
B.are asked what you would like to drink |
C.will be asked to have a chat with him or her |
D.are invited to take part in an afternoon tea party |
4.From the last paragraph (段落) we can see _______.
A. a new business was started in coffeehouses
B. coffeehouses are still used by businessmen and bankers
C. businessmen and bankers went to coffeehouses just for coffee
D. most people wouldn’t like to go to coffeehouses because of the noise
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