Finally, it should be pointed out that the artificial climatic environment created by air-conditioners canalso affect us. In a natural environment, whether indoor or outdoor, there aresmall variations in temperature and humidity. Indeed, the human body has long beenaccustomed to these normal changes. In an air-conditioned living or working environment,however, body temperatures remain well under37℃, our normal temperature. This leads to aweakened immune system and thus greater exposure to diseases such as colds and flu.

　　練習題：

　　Choose correct answers to the question:

　　1.What do we know about Legionnaire's disease from the passage?

　　A.It was the most widely concerned office hazard.

　　B.It can affect people both inside and outside the building.

　　C.It happens only in air-conditioned office buildings.

　　D.It does not develop in well-designed buildings.

　　2.In the old air-conditioned systems, bacteria first develop______.

　　A.in the reservoirs

　　B. in the ventilation system

　　c. in the humidifiers

　　D. in the air intake

　　3.The fact that about half of workers developed the ability to fight off the bacteriamay__.

　　A.relieve people’s worry about the danger caused by the bacteria

　　B.help people find an effective way to get rid of the bacteria

　　C.reflect the serious danger brought by the bacteria

　　D.cause serious disease such as cancers to people

　　4.The author most probably wants the readers to treat biocides with an attitude of_.

　　A.caution

　　B.trust

　　C.enthusiasm

　　D.criticism

　　5.The last paragraph implies that our immune system can be weakened when _•

　　A.we live in an artificial climatic environment

　　B.there are variations in temperature and humidity

　　C.our body temperatures often remain not high enough

　　D.we are often exposed to diseases such as colds and flu

　　1.[B] 事實細節題。本題主要考査復合句的理解。第2段最后一句表明B是正確選項。選項A中的most和C中的only都太絕對了，文中并未對選項A和C中的相關說法加以這樣的限定。選項D也太絕對了，第2段第3句只是說到“大多數情況下是因為空調設計欠佳所致”,并不是說所有設計良好的大廈就不會發生這種情況。

　　2.[A] 事實細節題。本題考查復合句的理解。只要明白第3段第2句這個非限制性定語從句中的the bottomsof which中的which是指上文的reservoirs,問題就不難解決了。

　　3.[C] 事實細節題。本題考查被動語態長句的理解。在第3段第3句中，關鍵詞是highlight,選項C是對原句主謂部分的近義替換。選項A和B在文中皆無提及，選項D是過度使用生物殺滅劑的后果，與本題干的情況無關。

　　4.[A] 觀點態度題。第3段最后兩句討論生物殺滅劑的用處，其中最后一句中的but, dangerous和cancers等詞說明作者認為要慎用這種殺滅劑。作者并沒對殺滅劑全盤否定，只是說過量使用會引發危險，因此選項D不對。

　　5.[C] 推理判斷題。本題考查代詞的理解。解題的關鍵在于理解最后一句中的This是指上一句所說的情況。選項A中所說的人造環境不是使免疫系統變弱的必然條件。選項B是保持免疫系統健康的條件。選項D是免疫系統變弱后的影響。