共用题干 The Dangers of Secondhand SmokeMost people know that cigarette smoking is harmful to their heal...

共用题干
The Dangers of Secondhand Smoke

Most people know that cigarette smoking is harmful to their health.Scientific research shows that it
causes many kinds of diseases.In fact,many people who smoke get lung cancer. However,Edward Gilson
has lung cancer,and he has never smoked cigarettes.He lives with his wife Evelyn,who has smoked about
a pack of cigarettes a day throughout their marriage.________(46)
No one knows for sure why Mr. Gilson has lung cancer. Nevertheless,doctors believe that secondhand
smoke may cause lung cancer in people who do not smoke because nonsmokers often breathe in the smoke
from other people's cigarettes.________(47)The US Environmental Protection Agency reports that about The smoke that comes from a lit cigarette contains many different poisonous chemicals.In the past,
scientists did not think that these chemicals could harm a nonsmoker's health._________(48)They
discovered that even nonsmokers had unhealthy amounts of these toxic chemicals in their bodies.As a matter
of fact,almost all of us breathe tobacco smoke at times,whether we realize it or not. For example,we can
not avoid secondhand smoke in restaurants,hotels and other public places.Even though many public places
have nonsmoking areas,smoke flows in from the areas where smoking is permitted.
It is even harder for children to avoid secondhand smoke._________(49)Research shows that chil-
dren who are exposed to secondhand smoke are sick more often than children who live in homes where no one
smokes and that the children of smokers are more than twice as likely to develop lung cancer when they are
adults as are children of nonsmokers.The risk is even higher for children who live in homes where both
parents smoke.
People are becoming very aware of the dangers of secondhand smoke._________（50) __________（49）