to huma n bein gs. This type of sleep gen erally occurs four or five times duri ng one ni ght of sleep lasti ng five minu tes to forty minu tes for each occurre nee. The deeper a pers on's sleep becomes, ~the Ion ger the periods of rapid eye moveme nt.
There are physical charges in the body to show that a pers on has cha nged from NREM( non-rapid eye moveme nt) to REM sleep. Breath ing becomes faster, the heart rate in creases, and, as the n ame implies, the eyes begi n to move quickly,
Accompa nying these physical cha nges in the body is a very importa nt characteristic of REM sleep. It is during REM sleep that a person dreams..
第 44 题 According to the passage,, how often does REM sleep occur in one n ight?
A. times
Once B.Twice C.Four or five D.Forty times
答案：C
第 45 题 The word \ng? ___________________
A.heavier. B.lo uder. C.str on ger. D.Happier.
答案：A
第 46 题 Which of the following shows that a person is NOT dreaming in
his sleep? ________
A.His eyes begi n to move.
B.His breath in g-becomes faster.
C.His heart rate in creases. 答案：D
D. His eyes stop movi ng.
第 47 题 The subject of this passage is ___________ .
A. why people sleep B.the huma n n eed for REM sleep
D.physical cha nges in the huma n body
C.the characteristic of REM sleep 答案：C
根据以下内容，回答下面试题。 Passage Four
Man's first real invention, and one of the most important inventions in history, was the wheel. All transportation and every machine in the world depe nd on it. The wheel is the simplest yet perhaps the most remarkable of all inven tio ns, because there are no wheels in n ature-no livi ng thing was ever created with wheels. How, then, did man come to invent the wheel? Perhaps some early hun ters found that they could roll the carcass of a heavy ani mal through the forest on logs more easily tha n they could carry it. However, the logs themselves weighed a lot.
It must have taken a great prehistoric thinker to imagine two thin slices of log connected, at their centers by a string stick. This would roll along just as the logs did, yet be much lighter and easier to han dle. Thus the wheel and axle came into being and with them the first carts.
第 48 题 The wheel is important because ___________ .
A.it was man's first real inven ti on B.all tran sportati on depe nds on it
C.every mach ine depe nds on it D.both B and C
答案：D
第 49 题 The wheel is called ___________ .
A. simple B.complicated C.stra nge D.unu sual
答案：D
第 50 题 It was remarkable of man to invent the wheel because ___________ .
A.
C.there were no wheels in n ature
it led to .ma ny other inven ti onsB.ma n had no use for it the n D.all of the above
答案：D
第 51 题 The wheel was probably inven ted by ___________ .
A.a group of early hun ters C.a great prehistoric thi nker 答案：A
根据以下内容，回答下面试题。 Passage Five
B.the first men on earth
D.the man who made the first cart
Eve n pla nts can run a fever, especially whe n they're un der attack by in sects or disease. But un like huma ns, pla nts can have their temperature take n from 3,000 feet away--straight up. A decade ago, adapti ng the in frared （
夕卜线）sca nning tech no logy developed for military purposes and other satellites,
physicist Stephe n Paley came up with a quick way to take the temperature of crops to determine which ones are under stress. The goal was to let farmers precisely target pesticide （ 杀虫剂）spraying rather than rain poison on a whole
field, which in variably in cludes pla nts that don't have pest （ 害虫）problems.
Eve n better, Paley's Remote Scanning Services Compa ny could detect crop problems before they became visible to the eye. Moun ted on a pla ne flow n at 3,000 feet at ni ght, an in frared sca nner measured the heat emitted by crops. The data were tran sformed into a color-code map show ing where pla nts were running\could the n spot-spray, using 50 to70 perce nt less pesticide tha n they otherwise would.
The bad n ews is that Paley's compa ny closed dow n in 1984, after only three years. Farmers resisted the new tech no logy and Ion g-term backers were hard to find. But with the renewed concern about pesticides on produce, and refinements in infrared scanning, Paley hopes to get back into operation. Agriculture experts have no doubt the tech no logy works~ \States\Departme nt of Agricultrue, thinks re- mote in frared crop sca nning could be adopted by the end of the decade. But only if Paley finds the financial backing which he failed to obta in 10 years ago.
第 52 题 In order to apply pesticide spraying precisely, we can use in frared sca nning
to ______________________ .
答案：A
A. ceded map
lo cate the problem areas B.drew a color-
C.measure the size of the affected area crops
D.estimate the damage to the
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