题目内容
When these women ________, they go on for hours.
- A.get talking
- B.get to talk
- C.have get talked
- D.have get to talk
此句可译作：这些女人一谈便是几个小时．句中的动词get作“reach the stage where one is doing sth. 达到(做某事)的阶段”解．表示进入某种状态，用作get doing．
华东师大版一课一练系列答案Batteries can power anything from small sensors to large systems. While scientists are finding ways to make them smaller but even more powerful, problems can arise when these batteries are much larger and heavier than the devices themselves. University of Missouri(MU) researchers are developing a nuclear energy source that is smaller, lighter and more efficient.
“To provide enough power, we need certain methods with high energy density(密度)”，said Jae Kwon, assistant professor of electrical and computer engineering at MU. “The radioisotope(放射性同位素) battery can provide power density that is much higher than chemical batteries.”
Kwon and his research team have been working on building a small nuclear battery, presently the size and thickness of a penny, intended to power various micro/nanoelectromechanreal systems (M/NEMS). Although nuclear batteries can cause concerns, Kwon said they are safe.
“People hear the word ‘nuclear’ and think of something very dangerous,” he said, “However, nuclear power sources have already been safely powering a variety of devices, such as pace-makers, space satellites and underwater systems.”
His new idea is not only in the battery’s size, but also in its semiconductor(半导体). Kwon’s battery uses a liquid semiconductor rather than a solid semiconductor.
“The key part of using a radioactive battery is that when you harvest the energy, part of the radiation energy can damage the lattice structure(晶体结构) of the solid semiconductor,” Kwon said, “By using a liquid semiconductor, we believe we can minimize that problem.”
Together with J. David Robertson, chemistry professor and associate director of the MU Research Reactor, Kwon is working to build and test the battery. In the future, they hope to increase the battery’s power, shrink its size and try with various other materials. Kwon said that battery could be thinner than the thickness of human hair.
【小题1】Which of the following is true of Jae Kwon?
| A．He teaches chemistry at MU. |
| B．He developed a chemical battery. |
| C．He is working on a nuclear energy source. |
| D．He made a breakthrough in computer engineering. |
| A．to show chemical batteries are widely applied. |
| B．to introduce nuclear batteries can be safely used. |
| C．to describe a nuclear-powered system. |
| D．to introduce various energy sources. |
| A．get rid of the radioactive waste | B．test the power of nuclear batteries. |
| C．decrease the size of nuclear batteries | D．reduce the damage to lattice structure. |
| A．uses a solid semiconductor | B．will soon replace the present ones. |
| C．could be extremely thin | D．has passed the final test. |
| A．science news report | B．book review |
| C．newspaper ad | D．science fiction story |
Plants are very important living things. Life could not go on if there were no plants. This is because plants can make food from air, water and sunlight. Animals and man cannot make food from air, water and sunlight. Animals get their food by eating plants and other animals. Therefore animals and man need plants in order to live. This is why we find that there are so many plants around us.
If you look carefully at the plants around you, you will find that there are two kinds of plants: flowering plants and non-flowering plants. Flowering plants can make seed. The seeds are protected by the fruits. Some fruits have one seed, some have two, three or four, and some have many seeds. But a few fruits have no seeds at all. An example of a fruit without seeds is the banana fruit. Most non-flowering plants do not grow from seeds. They grow from spores (胚芽). Spores are very small. Some spores are so small and light that they can float in the air. We may say that spores are quite the same as seeds. When these spores are all on wet and shady places, they usually grow into new plants.
【小题1】The main idea of the first paragraph is that ______.
| A．plants are important for life |
| B．plants cannot grow without air |
| C．there are many plants in the world |
| D．we can’t live without water |
| A．flower, water and air | B．water, sunlight and air |
| C．air, water and soil | D．air, sun and light |
| A．Of all living things animals are most important. |
| B．Spores are seeds. |
| C．All fruits of flowering plants have seeds. |
| D．Without plants, man will die out |
| A．a medicine book | B．a novel |
| C．a science magazine | D．an experiment report |
Often we take for granted the many household items we use every day. It is difficult to imagine there was a time in the past when these inventions did not exist. Actually, several of the most common inventions have been with us for quite some time. Inventions like toothbrush, contact lenses（隐形眼镜）, and credit cards came into use long ago.
The first toothbrush was introduced in China in the late 1400s but it was only 300 years later that this simple tool came into common use in Europe. By the nineteenth century, a variety of paste and powder cleaners were available throughout Europe as dental(牙齿的) care became more widespread. The first tube of toothpaste hit the market in Great Britain in 1891.
There is evidence to show that the first contact lenses were actually suggested by an astronomer, Sir John Herschel, in 1827. However, SirJohn Herschel was never able to create a working model of his idea. It was not until 1887 that a Swiss doctor from Zurich, Dr. Eugen Frick, came up with a workable process for producing precision (精密)lenses. Dr. Frick designed a new method for producing contact lenses,and the Zeiss factory in Germany began to produce contact lenses.
Credit cards have also been available for many years. They have been in use in the United States since the 1920s. At first, these cards were only used to buy gas in the quickly growing automobile service industry. Then, in the 1950s, Diners Club introduced the first general-purpose credit card. Today, credit cards such as Master Card, Visa, and American Express are commonly used by travelers around the world.
While it may be true that some of the greatest inventions and discoveries in history came about by chance, the majority of inventions that simplify our lives today came about through careful research and patient study. Of course, it still holds true that even with all the comforts of modern technology, inventors continue to search for ways of helping all of us get out of doing those necessary but tedious (乏味的) tasks which we still face. As the old saying goes, “Necessity is the mother of invention.”
【小题1】From the second paragraph we can learn that _____.
| A．toothbrushes came into common use in Europe in the 17th century |
| B．people could enjoy a variety of paste and powder cleaners in the 18th century |
| C．more and more people paid attention to dental care throughout Europe in the 19th century |
| D．the English could use different kinds of tubes of toothpaste in the early 19th century |
| A．Diners Club | B．Sir John Herschel |
| C．Dr Eugen Frick | D．the Zeiss factory |
A. Credit cards have a history of about two hundred years.
B. Three kinds of credit cards are being used in the USA.
C. The use of credit cards is closely related to the economic development.
D. American Express is only used by American travelers now.
【小题4】The last paragraph mainly tells us that ______.
| A．the greatest inventions came about by chance |
| B．inventions came about through careful research and patient study |
| C．inventors still continue to make inventions |
| D．necessity is the mother of invention |