19．Smoking bans in public places are linked with falls in childhood asthma （哮喘） attacks and preterm births （早產(chǎn)），according to the biggest analysis of the influence of public smoking bans on child health．The finding should remove fears that such laws could have the opposite effect because they may lead people to smoke more at home．
Several countries，such as Japan and Australia，have tightened laws on smoking in public places over the last few years．Meanwhile，some countries，such as the Netherlands and Germany，still allow smoking in pubs and restaurants．Only about half of US states have comprehensive bans，and there are few restrictions in poorer nations．
Opponents often claim that bans could result in people smoking more at home，which would be worse for their children's health．Asthma is one of the main concerns as second-hand smoke harms children's airways in several ways．
Researchers led by Jasper Been at Maastricht University Medical Centre reviewed as many as 11studies that examined how hospital admissions for childhood asthma and preterm births changed after smoking bans came in．The studies involved more than 2.5million births，and nearly 250，000hospital admissions for asthma．
The result shows that both asthma admissions and preterm birth rates fell by about 10percent within a year after smoking restrictions were carried out．The effect on preterm births could also have been caused by pregnant women being more likely to quit or cut down following a public ban，says Been．But Been also says the studies could not completely prove that smoking bans directly caused these changes．However，as a matter of fact，because the analysis included several smoking bans introduced in different countries in different years，and most saw health improvements．
Such findings are useful for countries and states where there is ongoing debate about how strict smoking bans should be，especially as hospital care for premature babies is so expensive．This might be one of the most important things to know in order to strengthen legislation （立法）．
Other studies have shown that rates of heart attack and stroke also tend to fall after smoking bans are introduced．
21．According to the passage，some oppose smoking bans in public places becauseB．
A．they have much difficulty in quitting smoking
B．they believe it will cause people to smoke more at home
C．smoking bans contributing to health can't be proved
D．the laws might cause opposite effect on smokers
22．Which is NOT the proper effect of the result of research by Jasper Been？C
A．People would accept the laws on smoking bans in public places．
B．More and more countries and states will strengthen smoking bans．
C．Hospital care for premature babies and asthma will be cheaper．
D．Pregnant women will be more likely to follow public smoking bans．
23．Which of the following statements about Been's research is TRUE？D
A．It also proves smoking bans lead to falls of heart attack and stroke．
B．It is related to millions of asthma hospital admissions and births cases．
C．It offers conclusive evidence about smoking bans causing health benefits．
D．It is supposed to prove the effect of smoking bans in public places on health．
24．In their analysis，the researchers drew their conclusion byA．
A．comparison
B．experimenting
C．questionnaire
D．example．
分析 本文是一篇社會文化類閱讀，屬于說明文，禁止在公共場合吸煙是與兒童哮喘發(fā)作和早產(chǎn)有關的，根據(jù)分析公共場所吸煙禁令對孩子健康的最大影響，應該這樣的法律會產(chǎn)生相反的效果，因為他們可能會導致人們更多的在家里抽煙．
解答 21．B 細節(jié)理解題．根據(jù)文章第3段"Opponents often claim that bans could result in people smoking more at home，which would be worse for their children's health"可知，反對者聲稱戒令會導致人們在家里多抽煙，從而更加影響孩子的健康，故選B項．
22．C 細節(jié)理解題．Jasper Been的研究結果表明A、B、D三項都是正確的；而哮喘和早產(chǎn)的住院治療費用的高低與此研究結果無關，故選C項．
23．D 推理判斷題．根據(jù)Researchers led by Jasper Been at Maastricht University Medical Centre reviewed as many as 11studies that examined how hospital admissions for childhood asthma and preterm births changed after smoking bans came in可知，由于人們對于公共場所戒煙是否會對健康造成影響存有疑慮，所以Been才會率領研究者進行研究，故選D項．
24．A 推理判斷題．根據(jù)第4、5段However，as a matter of fact，because the analysis included several smoking bans introduced in different countries in different years，and most saw health improvements．以及The effect on preterm births could also have been caused by pregnant women being more likely to quit or cut down following a public ban，says Been．But Been also says the studies could not completely prove that smoking bans directly caused these changes．可知，Been的研究主要是分析比較了不同國家戒煙前后兒童哮喘和早產(chǎn)住院數(shù)據(jù)而得出的結論，所以研究者采用的主要辦法就是比較，故選A項．
點評 本文是一篇社會文化類閱讀，題目涉及多道細節(jié)理解題，推理判斷題．做題時學生應仔細閱讀原文，把握文章主要內(nèi)容，聯(lián)系文章上下文內(nèi)容并結合所給選項含義，從中選出正確答案，一定要做到有理有據(jù)，切忌胡亂猜測．
