题目内容
The temperature of the sun is more than 5,000 degrees Fahrenheit at the surface, but it rises to perhaps more than sixteen million degrees at the center. The sun is so much hotter than the earth that matter can exist only as a gas, except at the core. In the core of the sun, the pressures are so great against the gases that, despite the high temperature, there may be a small solid core. However, no one really knows, because the center of the sun can never be directly observed.
Solar astronomers do know that the sun is divided into five layers or zones. Starting at the outside and going down into the sun, the zones are the corona, chromosphere , photosphere, convection and the sun has no solid surface, so it is difficult to tell where the atmosphere ends and the main body of the sun starts.
The sun's outermost layer begins about 10,000 miles above the visible surface and goes out ward for millions of miles. This is the only part of the sun that can be seen during an eclipse such as the one in February 1979. At any other time, the corona can be seen only when special instruments are used on cameras and telescopes to shot out glare of the sun's rays.
The corona is a bright, pearly white, filmy light, about as bright as the full moon. Its beautiful
rays are a sensational sight during an eclipse. The corona's rays flash out in a brilliant fan that has wispy (纤细的) spikelike rays near the sun's north and south poles. The corona is thickest at the sun's equator.
The corona rays are made up of gases streaming outward at tremendous speeds and reaching a temperature of more than two million degrees Fahrenheit. The rays of gas thin out as they reach the space around the planets. By the time the sun's corona rays reach the earth, they are weak and invisible.
The second paragraph is mainly concerned with ____________.
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Very little happened while Adams was President. It was an unhappy time for him, and he wasn't very effective, when his term ended, he went back to the Congress and served as a representative sentative(众议院议员). While he was in Congress, people began to respect him more than they had done while he was President. Adams was strongly against slavery and tried to outlaw it in Washington D.C.People began to look back on his presidency with a different view. Now they saw that he was an independent man with high ideal who loved his country and hated slavery Adams died in 1848 while speaking in the House of Representative.
When Adams served as the sixth U.S. President, ____________.
Most women in Ghana—the educated and illiterate(文盲) ,the urban and rural, the young and old—work to make money in addition to (此外，除了) maintaining their roles as housewives and mothers.
Ninety Percent women 15 years of age and over are married. Women say they would like to have six or more children, and in fact an average of seven children is born to every woman. In short, the normal life pattern for most Ghanaian women is to combine (结合)an active role in the economy(经济) with an active role as wife and mother of a large family.
How do these working mothers deal with their different roles in the home and on the job？ Some new ideas are being tried. One of these is family planning to help reduce family size. Another helpful measure is the day-care center, but usually the fees are too high for the poor. Ghanaians realize that more day-care centers are needed. Ghana today is looking for new ways to meet the needs of women and their families, so women can continue to play their roles both in the home and in the economy.
What's the main idea of paragraph 1 ？
It can be inferred from the passage that a clear view of the sun's outer layer is usually
Most people now forget the sinking of the great passenger ship Colossus exactly 60 years ago. The number of people who were actually saved was small, and some of those have died in the years since, so that those who are still alive today can be counted on the fingers of one hand. Then you will easily understand why I have been asked to write about that sad day in 1912. The Colossus, then she hit an iceberg in thick fog in the North Atlantic Ocean , she actually disappeared in less than twenty minutes, taking nearly fifteen hundred people with her. My own life was saved by my youth. Being only a boy of fourteen, I was one of those lucky women and children who, according to custom, were allowed to get away first from the sinking ship. The selfless crew packed some sixty of us into a small boat and lowered it into the angry sea. But during the ship's last minutes more and more passengers, as their last hope of escaping death, threw themselves wildly into the sea and tried to get on aboard our boat, with the result that it finally turned over and we all found ourselves struggling for our lives in the water. But I was strong enough to swim for three hours in the icy water before a passing ship picked me up.
This passage was written in ____________.
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