Question

    Smoking is harmful. But as soon as you quit the habit, everything will be OK, right? Wrong.

New research has found that even if you give up smoking, the damage it has done to your genes will stay there for a much longer time. In the research, a team of US scientists studied the blood of 16,000 people. Among them, some were smokers, some used to smoke, and the rest were non-smokers. Scientists compared their genes and found that more than 7,000 genes of smokers had changed－a number that is one-third of known human genes.

According to NBC News, both heart disease and cancer are caused by genetic changes. Some people may have had the changes when they were born, but most people get them in their day-to-day lives while doing things like smoking.

When you stop smoking, a lot of these genes will return to normal within five years.

This means your body is trying to heal (治愈) itself of the harmful effects of smoking. But the changes in some of the genes stay for longer. They can stay for as long as 30 years, It’s almost like leaving a footprint on wet cement (水泥)－it will always be there, even when you’ve walked away and when the cement becomes dry.

Although the study results may make people unhappy, there is a bright side: the findings could help scientists invent medicine to treat genetic damage caused by smoking or find ways to tell which people have heart disease or cancer risks.

1.The purpose of Paragraph 1 is to______ .

A.raise a question B.give an example

C.make an argument D.show the main idea of the passage

2.Most genetic changes happen because of______ .

A.people’s condition at birth B.environmental pollution

C.heart disease and cancer D.people’s bad living habit

3.The underlined word “it” in Paragraph 5 refers to______ .

A.the footprint B.the cement

C.the harmful effect D.the genetic change

4.Which of the following statements is true?

A.The findings are the fruit of more than three years’ research.

B.The findings have prevented more people from starting smoking

C.The findings offer evidence that a damaged gene can heal itself.

D.The findings help to find cures for genetic damage caused by smoking.

Answer

1.D

2.D

3.A

4.D

【解析】

这是一篇说明文。作者通过文章主要向我们描述了研究发现即放弃吸烟对基因的损害也是无法挽回的。

1.

推理判断题。根据文章第一段Smoking is harmful. But as soon as you quit the habit, everything will be OK, right? Wrong（吸烟是有害的。但是一旦你戒了这个习惯，一切都会好起来的，对吧?错了）可知，这段在介绍了文章的主题----即使放弃吸烟的习惯，它的危害性还是存在的。故选D项。

2.

细节理解题。根据文章第三段Some people may have had the changes when they were born, but most people get them in their day-to-day lives while doing things like smoking（有些人可能在出生时就有这种变化，但大多数人是在日常生活中吸烟时产生的）可知，大多数遗传变化是因为人们的不良生活习惯导致的。故选D项。

3.

词义猜测题。根据文章倒数第二段They can stay for as long as 30 years, It’s almost like leaving a footprint on wet cement－it will always be there, even when you’ve walked away and when the cement becomes dry（它们可以存在长达30年之久，就像在未干的水泥上留下了一个脚印——它永远在那里，即使你离开了，水泥变干了）可知，此处的it应指代破折号前的“脚印”。故选A项。

4.

细节理解题。根据文章最后一段Although the study results may make people unhappy, there is a bright side: the findings could help scientists invent medicine to treat genetic damage caused by smoking or find ways to tell which people have heart disease or cancer risks（尽管这项研究结果可能会让人们不开心，但它也有好的一面:这项发现可以帮助科学家发明治疗吸烟引起的基因损伤的药物，或者找到辨别哪些人有心脏病或癌症风险的方法）可知，这些发现有助于找到吸烟引起的基因损伤的治疗方法。故选D项。