we have to deter- mine whether there are a limited number of genes in cells which are always responsible for at leasl part of the trouble. If we can understand how cancer works, we can counteract its action. "
63. The example of Pasteur in the passage is used to__.
A. predict that the secret of cancer will be disclosed in a decade
B. indicate that the prospects for curing cancer are bright
C. prove that cancer will be cured in fifty to sixty years
D. warn that there is still a long way to go before cancer can be conquered
64. The author implies that bv the year 2000 ,__.
A. there will be a drastic rise in the five-year survival rate of skin-cancer patients
B. 90 percent of the skin-cancer patients today will still be living
C. the survival statistics will be fairly even among patients with various cancers
D. there won' t be a drastic increase of survival rate of all cancer patients
65 . Oncogenes are cancer-causing genes__.
A. that are always in operation in a healthy person
B. which remain unharmful so long as they are not activated
C. that can be driven out of normal cells
D. which normal cells can' t turn off
66 . The word "dormant" in the third paragraph most probably means__.
A. dead B. ever-present C. inactive D. potential
Passage 5
Discoveries in science and technology are thought by "untaught minds" to come in blinding flashes or as the result of dramatic accidents. Sir Alexander Fleming did not, as legend would have it, look at the mold (霉) on a piece of cheese and get the idea for penicillin there and then.
He experimented with antibacterial substances for nine years before he made his discovery. Inven- tions and innovations almost always come out of laborious trial and enor. Innovation is like soc- cer; even the best players miss the goal and have their shots blocked much more frequently than
they score.
The point is that the players who score most are the ones who take most shots at the and so it goes with innovation in any field of activity. The prime difference between innovation and others is one of approach. Everybody gets ideas, but innovators work consciously on theirs, and they follow them through until they prove practicable or otherwise. What ordinary people see as fanciful abstractions , professional innovators see as solid possibilities.
"Creative th
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