题目内容
To this happening again, John suggested that the source of all the water supplies .
A, stop, be examined B, keep, should be examined
C, prevent, examined D, stop, was examined
A
解析
赢在课堂名师课时计划系列答案
天天向上课时同步训练系列答案It is natural that children are curious (好奇的) about the world around them. For example, they want to know how their hearts beat. They want to know why the ocean water tastes salty.
As children grow up, they become curious about different kinds of things. When they are babies, they are interested in the parts of their bodies and in the smiles of their mothers. They become interested in the physical world around them: the plants, the animals, the sky. Later, they become interested in the things that people have made: wheels, bicycles, cars. And when they are adults, their curiosity continues. Sometimes this curiosity leads to a career (生涯、职业) in science.
Scientists spend their lives trying to find out about the world. Those who work with the earth sciences study the earth, the oceans, and the skies. Other scientists who study living things work with the biological sciences. A third group of scientists study the physical sciences, e. g. physics, chemistry .
These scientists have already discovered a lot about our world. For example, they tell us why your heart beats fast when you run. They say that when you are quiet, your heart normally beats sixty-five or seventy-five times a minute. Your heart is a pump (泵) that pumps blood to all parts of the body. The blood carries oxygen and nutrition. When you run, your muscles work very hard and use the nutrition that the blood carries to them. The muscles need oxygen, too . So your brain sends a signal to the heart. The signal means that the muscles need more nutrition and oxygen. Then the heart beats fast and sends blood quickly to the muscles. It may beat 90 to 140 times a minute.
Of course, scientists cannot answ
er all of our questions. If we ask, “Why does the ocean water taste salty” scientists will say that the salt comes from rocks. When a rock gets very hot or very cold, it cracks. Rain falls into cracks. The rain then carries the salt into the earth and into the rivers. The rivers carry the salt into the ocean. But then we ask , “What happens to the salt in the ocean? The ocean does not get saltier every year.” Scientists are not sure about the answer to this question.
We know a lot about our world, but there are still many answers that we do not have, and we are curious.
【小题1】According to the passage, which of the following statements is true?
| A．People are curious in the same way. |
| B．People in different countries are interested in different things. |
| C．Men and women are curious about different things. |
| D．People of different ages are interested in different things |
| A．the earth , the oceans and the sky | B．man-made things |
| C．plants and animals | D．ocean water |
| A．more nutrition and oxygen | B．more signals |
| C．more salt | D．water |
| A．in wet regions | B．in dry regions |
| C．at very high or very low temperatures | D．when salty water falls in |
| A．they cannot explain many things | B．they know nothing about the world |
| C．they know little about the world | D．they want to be scientists |
Self-employed private physicians who charge a fee for each patient visit are the foundation of medical practice in the United States. Most physicians have a contract relationship with one or more hospitals in the community. They send their patients to this hospital, which usually charges patients according to the number of days they stay and the facilities(operating room, tests, medicines that they use). Some hospitals belong to a city, a state or, in the case of veteran's hospitals, a federal government agency. Others are operated by religious orders(教会) or other non-profit groups.
Some medical doctors are on salary. Salaried physicians may work as hospital staff members, or residents, who are often still in training. They may teach in medical schools, be hired by corporations to care for their workers or work for the federal government's Public Health Service.
Physicians are among the best paid professionals in the United States. In the 1980s, it was not uncommon for medical doctors to earn incomes of more than $ 100 000 a year. Specialists, particularly surgeons, might earn several times that amount. Physicians list many reasons why they deserve to be so well rewarded for their work. One reason is the long and expensive preparation required to become a physician in the United States. Most would-be physicians first attend college for four years, which can cost nearly $ 20 000 a year at one of the best private institutions. Prospective physicians then attend medical school for four years. Tuition alone can exceed $ 10 000 a year. By the time they have obtained their medical degrees, many young physicians are deeply in debt. They still face three to five years of residency(实习阶段) in a hospital, the first year as an apprentice physician. The hours are long and the pay is relatively low.
Setting up a medical practice is expensive, too. Sometimes several physicians will decide to establish a group practice, so they can share the expense of maintaining an office and buying equipment. These physicians also take care of each other's patients in emergencies.
Physicians work long hours and must accept a great deal of responsibility. Many medical procedures, even quite routine ones, involve risk. It is understandable that physicians want to be well rewarded for making decisions which can mean the difference between life and death.
【小题1】 According to the passage, it is very unlikely that an American hospital is owned by ______.
| A．a church | B．a corporation | C．a city | D．a state |
| A．schooling and retraining | B．practice in a hospital |
| C．facilities he or she uses | D．education he or she receives |
| A．About seven years. | B．Eight years. | C．Ten years. | D．About twelve years. |
| A．there are so many patients that it is difficult for one physician to take care all of them |
| B．they can take turns to work long hours |
| C．facilities may be too much of a burden for one physician to shoulder |
| D．no one wants to assume too much responsibility |
| A．For their expensive education and their responsibility, they deserve a handsome pay. |
| B．It is reasonable for physicians to have a large income because their work is very dangerous. |
| C．Physicians should be better paid because they work long hours under bad conditions. |
| D．Physicians have great responsibility, so it is understandable that they should be well rewarded. |
Ears are for hearing — everyone knows that. But for a creature called the Cuvier’s beaked whale, hearing starts in the throat (喉咙), a new study found.
The observation might help explain how all whales hear. The work might also help scientists understand how animals are affected by underwater sonar (声呐). This sonar, used by some ships, sends out sound waves to locate underwater objects.
The Cuvier’s beaked whale is a so-called toothed whale. Toothed whales dive deep into the ocean in search of food. As the whales hunt, they produce sounds that reach objects and then return to the whales. This allows the animals to “see” the shape, size, and location of objects, even when they’re 1,000 meters under the sea, where it is totally dark.
To better understand how the whale hears, researchers from San Diego State University in California took X rays of two Cuvier’s beaked whales. The whales had died and washed up on the beach.
Ted Cranford and his colleagues used the images to make a computer model of a Cuvier’s b
eaked whale’s head. Then, they modeled the process of sound traveling through the head.
The researchers knew that some sounds get to the ears of a toothed whale through a structure (构造) called “the window for sound”. Found on the lower jaw, this structure is very thin on the outside and has a large pad (垫) of fat on the inside.
When the researchers used their computer model to work out how sound waves travel in the whale’s head, they were surprised to find that sounds coming from right in front of the whale actually travel under the animal’s jaw. From there, sound waves move through the throat, into a hole in the back of the jaw, and finally to the pad of fat near the animal’s ears.
【小题1】Toothed whales look for food under the sea by ______.
| A．watching the shape and size of their objects | B．diving deep into the sea |
| C．sending and receiving sounds | D．making lots of noises |
| A．find out why they had died and washed up on the beach |
| B．make a computer model of a Cuvier’s beaked whale’s head |
| C．make sure that sound travels through the head |
| D．know more about the way the whale hears |
| A．A hole in the back of the jaw → the ears → the jaw → the throat. |
| B．The jaw → the throat → a hole in the back of the jaw → the ears. |
| C．The throat → the jaw → the ears → a hole in the back of the jaw. |
| D．The ears → the throat → a hole in the back of the jaw → the jaw. |
| A．The throat is important to the Cuvier’s beaked whale’s hearing. |
| B．Ships send out sound waves like a Cuvier’s beaked whale. |
| C．The ears are actually useless to the Cuvier’s beaked whale. |
| D．The researchers haven’t found how the whales hear. |
To us it seems so natural to put up an umbrella to keep the water off when it rains, but actually the umbrella was not invented as protection against the rain, Its first use was as a shade against the sun!
Nobody knows who first invented it, but the umbrella was used in very ancient times. Probably the first to use it were the Chinese in the 11th century BC.
We know that the umbrella was used in ancient Egypt and Babylon as a sunshade. And there was a strange thing connected with its use: it became a symbol of honor. In the Far East in ancient times, the umbrella was allowed to be used only by those in high office.
In Europe, the Greeks were the first to use the umbrella as a sunshade. And the umbrella was in commonly used in ancient Greece. But it is believed that the first persons in Europe to use the umbrella as protection against the rain were the ancient Romans.
During the Middle Ages, the use of the umbrella practically disappeared. Then it appeared again in Italy in the late sixteenth century. And again it was considered as a symbol of power. By 1680, the umbrella appeared in France and later in England.
By the eighteenth century, the umbrella was used against rain throughout most of Europe.
Umbrellas have not changed much in style during all this time, though they have become much lighter in weight. It wasn’t until the twentieth century that women’s umbrellas began to be made , in a whole variety of colors.
【小题1】According to this passage, the umbrella was probably first invented in ancient_______.
| A．China | B．Egypt | C．Greece | D．Rome |
| A．No one exactly knows who the inventor of the umbrella was |
| B．The umbrella was first invented to be used as protection against the sun. |
| C．The umbrella changed much in style in the eighteenth century |
| D．In Europe, the Greeks were the first to use the umbrella as a sunshade. |
| A．protection against rain | B．a symbol of honor and power |
| C．a shade against the sun | D．women’s decoration |
| A．during the Middle Ages | B．in Rome | C．by the 18th | D．in Greece |
| A．when and how the umbrella was invented |
| B．why the umbrella was so popular in Europe |
| C．the development of the umbrella |
| D．The history and use of the umbrella |