题目内容
Many theories about the origin of the ocean have been proposed by scientists. The most widely accepted one is that the earth at some time in its very early history became hot enough to melt the materials from which it was formed. While in this molten state, lighter rock-forming materials (造岩材料) floated on the surface of the heavier ones. Then, between four and a half four billion (十亿) years ago, the molten earth cooled sufficiently to form. a crust of rock that was many miles thick.
Surrounding the earth was an unbroken canopy of clouds miles thick and made up mostly of water vapor. Rain falling toward the still-hot earth was heated to steam and rose to the clouds again. After many millions of years, as the earth continued to cool, its surface temperature fell below the boiling point of water. Rainwater could now remain on the earth, covering its whole surface except for the higher places on earth that had been formed from the lighter rock materials.
In 1970, scientists had pieced together evidence that the lighter rock materials had formed one huge continent by a vast ocean. Then, about 200 million years ago, the great continent began to break up, the pieces moving slowly apart.
The onrushing waters of the single huge ocean now entered and filled the spaces between the separating continents--and became the several oceans and seas we know today.
This passage mainly talks about ______.
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If you are like most people, your intelligence varies from season to season. You are probably a lot sharper in the spring than you are at any other time of year. A noted scientist, Ells- worth Huntington (1876-1947) concluded from other men's work and his own among peoples in different climates that climate and: temperature have a definite effect on our mental abilities.
He found that cool weather is much more favorable for creative thinking than summer heat is. This does not mean that all people are less intelligent in the summer than they are during the rest of the year. It does mean, however, that mental, abilities of large numbers of people tend to be lowest in the summer.
Spring appears to be the best period of the year for thinking. One reason may be that in the spring man's mental abilities are affected by the same factors that bring about great changes in all nature.
Fall is the next best season, then winter. As for summer, it seems to be a good time to take a long vacation from thinking!
According to the passage, your mental ability ______.
In the 1900's, American townspeople usually washed and brushed their teeth and combed their hair in the kitchen. Or they kept a water pitcher (大水罐) and a wash basin in their rooms and took care of these things there.
The bathtub was a wash tub (澡盆) filled with water from the stove. If you were small enough you could sit down by drawing your knees to your chest, Otherwise, you washed yourself standing up. Often all the women and girls in the family bathed together. Then the men and boys did. In most families this was Saturday-night because Sundays they went to church.
A small number of families did have running water. But that depended on Whether there was a water system where they lived and on whether they could afford the plumbing (水管实施 ). Some people had bathtubs in their homes as early as 1895. But many others did not have their first bath in a bathtub until 1910 or later when they were fifteen or sixteen years old.
In the first paragraph, "took care of" means ______.
统一指挥原则强调命令的统一和水平的管理系统。()
Section B
Directions: There are 2 passages in this section. Each passage is followed by some questions or unfinished statements. For each of them there are four choices marked A, B, C and D. You should decide on the best choice.
It is difficult to imagine what life would be like without memory. The meanings of thousands of everyday perceptions, the basis for the decisions we make, and the roots of our habits and skills are to be found in our past experiences, which are brought into the present by memory.
Memory can be defined as the capacity to keep information available for later use. It not only includes "remembering" things like arithmetic or historical facts, but also involves any change in the way an animal typically behaves. Memory is involved when a rat gives up eating grain because he has sniffed (嗅出) something suspicious in the grain pile.
Memory exists not only in humans and animals but also in some physical objects and machines. Computers, for example, contain devices for storing data for later use. It is interesting to compare the memory storage capacity of a computer with that of a human being. The instant access memory of a large computer may hold up to 100,000 "words"--string of alphabetic or numerical characters--ready for instant use. An average U.S. teenager probably recognizes the meaning of about 100,000 words of English. However, this is but a fraction of the total amount of information that the teenager has stored. Consider, for example, the number of faces and places that the teenager can recognize on sight.
The use of words is the basis of the advanced problem-solving intelligence of human beings. A large part of a person's memory is in terms of words and combinations of words. But while language greatly expands the number and the kind of things a person can remember, it also requires a huge memory capacity. It may well be this capacity that distinguishes humans, setting them apart from other animals.
Which of the following is TRUE about memory？
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