DDT, the most powerful pesticide the world had ever known, exposednature’s

游客2023-12-13  33

问题     DDT, the most powerful pesticide the world had ever known, exposed
nature’s vulnerability. Unlike most pesticides, which effectiveness is limited (1)______
to destroy one or two types of insects, DDT was capable of killing hun- (2)______
dreds of different kinds at once. Developed in 1939, it first distinguished
itself during World War II, cleaning South Pacific islands of malaria- (3)______
caused insects for U.S. troops, while in Europe being used as an effective (4)______
de-lousing powder. Its inventor was awarded by the Nobel Prize. (5)______
    When DDT became available for civilian use in 1945, there were only
a few people who expressed the second thoughts about this new miracle (6)______
compound. One was nature writer Edwin Way Teale, who warned, "A spray
as discriminate as DDT can upset the economy of nature as much as a revo- (7)______
lution upsets social economy. Ninety percent of all insects are good, but if (8)______
they are killed, things go out of kilter right away." Another was Rachel Car
son, who wrote to the Reader’s Digest to propose an article about series of (9)______
tests on DDT being conducted not far from which she lived in Maryland. (10)______
The magazine rejected the idea. [br] (8)

选项

答案 but — and

解析 这里如果使用but,句子的连接就不很顺畅。实际上本句的两个意群的关系应该是顺接,而不是转折,因此应选用表顺接的连词,如and和so等。
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