Many people die for their revolutionary （)

A . supply B . offer C . provide D . yield

A、isolation B、life expectancy C、burnout D、electro smog

A、nod B、shave C、wave D、shake

A．True B．False

A.successful big company． B.successful small company． C.successfuI smalI businesses．

A．cater B．supply C．provide D．equip

A．A. terrifies B．B. curses C．C. puzzles D．D. injures

The human body demands that the amount of salt in the blood always stay the same.When the body does not get enough salt, it protects itself by letting less salt leave the body in urine and sweat. But it cannot reduce this output to zero. Some salt is always escaping. On a completely saltless diet, like that of some people in Africa, the body steadily loses small amounts of salt through the kidneys (肾) and sweat glands (腺). It then tries to ad-just to this loss by speeding up its secretion (分泌) of water. In this way, the body attempts to keep the amount of salt in the blood at the necessary level. The result is a slow drying up of body and, finally, death. The person dies of thirst. In cases where there is little or no water to drink, the body tries to do the opposite thing. Again, it must keep the salt level in the blood constant. Because it has little water, it attempts to stop water from leaving the body and to increase its secretion of salt. But, as with the escaping salt, it cannot be completely successful. Some water still leaves and the person eventually dies of thirst. In short, the body's normal needs for salt and for water are both parts of the same important need to keep the salt level in the blood constant. Some African people once drank animal urine______. A．when they were going to die B．because they were thirsty C．because there was little salt D．because they were short of water

A．The development of resistance to diseases. B．The difficulty to cure new emerging diseases. C．The inability of the poor to afford medicine.

In ancient Mexico there were many clearings in the forest. In each clearing was a village with fields of different crops around it. The Maya cut down trees with stone axes and planted seeds by digging holes in the ground with pointed sticks. A farmer was able to grow crops that produced food for several people. But not every Maya had to be a farmer. Some were cloth makers, builders, or priests. The Maya believed in many gods. The people built large temples to honor their gods. Skillful workers built cities around these temples. It was difficult to construct these cities, because they had no horses to carry the heavy stone needed. Workers had to carry the building materials themselves. Today, many of these ancient Mayan cities and temples are still standing. Measuring time was important to the Maya, so they developed a system for measuring it accurately. Farmers needed to know when to plant and harvest their crops. Mayan priests made a system to keep track of time. They wrote numbers as dots (...) and bars (- ). A dot was one and a bar was five. The Mayan priests studied planets. They made a calendar from what they learned. The year was divided into. 18 months of 20 days each with five days left over. The Mayan calendar was far more accurate than the European calendars of the time. Around the year 800, the Maya left their villages and beautiful cities, never to return. No one knows why. They may have died from an infectious disease. They may have left because the soil could no longer grow crops. Archaeologists are still trying to find the lost secrets of the Maya. They are still one of our greatest mysteries. This article may be taken from ______. A．a magazine B．a literature book C．an art book D．a historical book

A、assistance B、existence C、persistence D、resistance

A．residence B．persecution C．enquiry D．ignorance

A．one B．two C．three D．four

A．poor defense skill B．obsession with advertising C．empty promise of huge compensation D．craze about winning

One important cause of the generation gap is the opportunity that young people have to choose their own ways of life.In a more traditional society, when children grow up, they are expected to live in the same area as their parents, to marry people that their parents know and like, and often to continue the family jobs.In our society, young people often travel great distances for their education, move out of the family at an early age, marry or live with people whom their parents have never met, and choose jobs different from those of their parents. In our society, parents often expect their children to do better than they did, to find better jobs, to make more money and to do all the things that they were unable to do.Often, that is another cause of the gap between them.Often, they discover that they have very little in common with each other. Finally, the speed at which changes take place in our society is the third cause of the gap between the generations.In a traditional culture, senior people are valued for their knowledge, but in our society the knowledge of a lifetime may become out of date.The young and the old seem to live in two very different worlds, separated by different skills and abilities.No doubt, the generation gap will continue in American life for some time to come. 1.The first paragraph tells us that ______. A、the problem of the generation gap draws much attention from people B、it is out of date to talk about the generation gap C、children and parents are trying to understand each other D、it is very important for people to frequently communicate with each other 2.In a more traditional society, old people_______. A、have their children respect and listen to them B、do not care for their children at all C、expect their children to rebel against them D、do not live together with their children 3.In American society young people________. A、do not need to find jobs B、leave home at an early age C、have better education than their parents D、marry people younger than them 4.Which of the following is NOT the cause of the generation gap______. A、Young people like to depend more on themselves. B、Parents do not love their children dearly. C、American society changes rapidly. D、Parents expect too much of their children. 5.The main idea of the passage is ________. A、that the generation gap needs considering B、when the generation gap is necessary in American society C、why the generation gap exist D、how we can reduce the generation gap

是 否