Passage Two
Questions 62 to 66 are based on the following passage.
For many years, scientists couldn't figure out how atoms and molecules on the Earth combined to make living things. Plants, fish, dinosaurs, and people are made of atoms and molecules, but they are put together in a more complicated way than the molecules in the primitive ocean. What's more, living things have energy and can reproduce, while the chemicals on the Earth 4 billion years ago were lifeless.
After years of study, scientists figured out that living things, including human bodies, are basically made of amino acids and nucleotide bases. These are molecules with millions of hydrogen, carbon, nitrogen, and oxygen atoms. How could such complicated molecules have been formed in the primitive soup? Scientists were stumped.
Then, in 1953, two scientists named Harold Urey and Stanley L. Miller did a very simple experiment to find out what had happened on the Primitive Earth. They set up some tubes and bottles in a closed loop, and put in some of the same gases that were present in the atmosphere 4 billion years ago: water vapor, ammonia, carbon dioxide, methane, and hydrogen.
Then they shot an electric spark through the gases to simulate bolts of lightning on the ancient Earth, circulated the gases through some water, sent them back for more sparks, and so on. After seven days, the water that the gases had been bubbling through had turned brown. Some new chemicals were dissolved in it. When Miller and Urey analyzed the liquid, they found that it contained amino acids-the very kind of molecules found in all living things.
62. When did scientists come to realize how the atoms and molecules on the Earth combined to make living thing?
A) 4 billion years ago. B) In 1953.
C) After seven days. D) Many years later.
63. Scientists figured out that human bodies are basically made of .
A) amino acids
B) molecules
C) hydrogen, carbon, nitrogen and oxygen atoms
D) water vapor, ammonia, carbon dioxide, methane and hydrogen
64. Harold Urey and Stanley L.Miller did their experiment in order to .
A) find out what had happened on the Earth 4 billion years ago
B) simulate bolts of lightning on the ancient Earth
C) dissolve some new chemicals
D) analyze a liquid
65. At the end of the last paragraph, the word "it" refers to .
A) a closed loop B) an electric spark C) water D) the liquid
66. According to the writer, living things on the Earth include .
A) atoms and molecules B) chemicals
C) plants, fish, dinosaurs and human beings D) the primitive soup
[5] 完形填空
Part ⅤCloze(15 minutes)
Directions:There are 20 blanks in the following passage. For each blank there are four choices marked A), B), C) and D) on the right side of the paper. You should choose the ONE that best fits into the passage. Then mark the corresponding letter on the Answer Sheet with a single line through the centre.
Robert Edwards 67 in an unusual accident many years 68 .He was also partially deaf 69 old age.Last week he was walking near his home 70 a thunderstorm 71 .He took shelter 72 a tree and was struck by lightning.He was 73 to the ground and woke up 74 20 minutes later, 75 face down in water below a tree.He went into the house and lay down in bed.A short time later he awoke.His legs couldn't move 76 he was trembling. 77 ,when he opened his eyes he could see the clock 78 the room in front of him. 79 his wife entered he saw her for the first time in nine years. Doctors confirmed that he had 80 his sight and hearing apparently 81 the flash of lightning.But they were unable to explain the 82 . One possible explanation 83 by one doctor was that Edwards lost his sight 84 a hard blow in a terrible accident.Perhaps the only way it could 85 was by 86 blow.
67. A) blinded B）was blinded
C）had been blind D）had been blinded
68. A) later B）before C）ago D）early
69. A) because of B）because
C）at D）in
70. A) when B）while C）until D）where
71. A) fell B） blew
C）formed D）approached
72. A) in B）on C）under D）near
73. A) thrown B）knocked C）fallen D）beaten
74. A) just B）some C）for D )within
75. A) to lie B）having lain
C）lay D）lying
76. A) and B） when C） but D） while
77. A) Thus B） Therefore C） But D） Above all
78. A) across B） through C） into D） out of
79. A) While B） When
C）Whenever D）As
80. A) gained B）gotten
C） reminded D）regained
81. A) at B）in C）from D） on
82. A) result B）reason
C）consequence D）content
83. A) offered B）contributed
C）sought D) thought
84. A) because of B）owing to
C）based on D）as a result of
85. A) restore B）be restored
C）have restored D）have been restored
86. A) other B） the other C）another D）one
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