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The moon, being much nearer to the Earth than the Sun, is the ____ cause of the tides.
A. principal B. basic C. initial D. elementary
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A. principal B. basic C. initial D. elementary
The sun also exerts its effect on the tide, being a lit fie less than half as much as the moon, although its mass is so much greater. When the moon and the sun are horizontal, the highest high tide occurs and when they are vertical the lowest low tide takes place.
The wind also plays an important part in the modification of the normal rise and fall of the tide. Thus these factors affect each other, either detracting or adding to the attractive forces to add or subtract from the weight of the tide. But the tides still move inexorably on, rising twice a day, getting a little later each day and posing a problem of correctly predicting their heights and lows.
Which of the following factors will not affect the time of the tide?
A.The position of the sun and the moon.
B.The mass of the moon.
C.The wind.
D.All of the above mentioned factors.
The marvel of the machine age, the electronic computer has been in use only since 1946. It can do simple computations—add, subtract, multiply, and divide—with lightning speed and perfect accuracy. It can multiply two 10-digit numbers in 1/1, 000 second, a problem that would take an average person five minutes to do with pencil and paper. Some computers can work 500, 000 times faster than any person can.
Once it is given a program, that is, a carefully worked-out set of instructions devised by a technician trained in computer language, a computer can gather a wide range of information for many purposes. For the scientist it can get information from outer space or from the depths of the ocean. In business and industry the computer prepares factory inventories, keeps track of sales trends and production needs, mails dividend checks, and makes out company payrolls. It can keep bank accounts up to date and make out electric bills. If you are planning a trip by plane, the computer will find out what route to take and what space is available.
Why does the author regard the electronic computer as the marvel of the machine age?
A.Because electronic computers are rare.
B.Because people know little about electronic computers.
C.Because electronic computers can do much more kinds of work that human beings can't.
D.Because electronic computers have been widely suspected.
The moon is about 384 000 kilometers away from the earth. A plane can not fly to the moon because the air reaches only 240 kilometers high above the earth. Then there is no air. But something can fly even when there is no air. That is' a rocket (火箭).
Rockets can fly out into space. Rockets with men in them have already reached the moon. Some rockets without men in them have flown to other parts, much farther away from the earth than the moon in the universe. One day, rockets may be able to go to any place.
Scientists knew ______ about the moon a long time ago.
A.nothing
B.many things
C.everything
D.little
Passage Two
Questions 26 to 30 are based on the following passage.
Tides are created mainly by the pull of the moon on the earth. The moon's pull causes water in the oceans to be a little deeper at a point closest to the moon and also at a point farthest from the moon, on the opposite side of the earth. These two tidal “waves” follow the apparent movement of the moon around the earth and strike nearly every coast line at intervals of about twelve hours and twenty-five minutes. After reaching a high point, the water level goes down gradually for a little more than six hours and then begins to rise toward a new high point. Hence, most coast lines have two tides a day, and the tides occur fifty minutes later each day. Differences in the coast line and in channels in the ocean bottom may change the time that the tidal wave reaches different points along the same coast line. The difference in water level between high and low tide varies from day to day according to the relative positions of the sun and the moon. The sun also exerts a pull on the earth, although it is only about haft as strong as the pull of the tides arise higher and when they pull at right angles to one another. the tide is lower. The formation of the coast line and variations in the weather are additional factors which can affect the height of tides. Some sections of the coast are shaped in such a way as to cause much higher tides than are experienced in other areas. A strong wind blowing toward the shore may also cause tides to the higher.
Which of the following is right according to the passage?
A. Some coast lines do not have two tides each day.
B. Tides are not affected by the shape of coast line.
C. The sun has as much effect on tides as does the moon.
D. Tides usually rise to the same land day after day.
acted much attention.
A) Being published B) Published
C) Publishing D) To be published
A.that he claims
B.does he claim
C.as he claims
D.is it that he claims
The children born in the United States today______.
A.will avoid being threatened by the tremendous medical progress
B.have as much chance of survival as before
C.will probably live to be seventy years old
D.have much more chance of survive than that of death
A.the computer' s memory has a little bigger capacity than a teenager' s
B.the computer' s memory capacity is much smaller that an adult human being' s
C.the computer' s memory capacity is much smaller even than a teenager' s
D.both A and B
A as B which C that D what
The reason why many big hotels are being torn down is that______.
A.more and more travelers choose to stay in motels
B.people want to spend their time in a more quiet place
C.it costs too much money for people to stay in a hotel
D.cities have become short of land for building large hotels
A. is being measured successfully
B. is constantly making changes
C. is receiving much radical consideration
D. is increasingly getting challenged