问题 判断题

吸烟会影响呼吸系统的健康,长期吸烟会引起癌症。

答案

题目分析:香烟中含有1400多种成分.吸烟时产生烟雾里有40多种致癌物质,还有十多种会促进癌发展的物质,其中对人体危害最大的是尼古丁、一氧化碳焦油和多种其它金属化合物.一支烟所含的尼古丁就足以杀死一只小白鼠.香烟烟雾中大量的一氧化碳同血红蛋白的结合能力比氧大240-300倍,严重地削弱了红细胞的携氧能力,因此,吸烟使血液凝结加快,容易引起心肌梗塞、中风、心肌缺氧等心血管疾病.更为严重的是,吸烟者还严重妨碍他人健康.研究结果表明,吸烟者吸烟时对旁人的危害比对他自己还大.有关医学研究表明,吸烟是心脑血管疾病、癌症、慢性阻塞性肺病等多种疾患的行为危害因素,吸烟已成为继高血压之后的第二号全球杀手.据统计,长期吸烟者的肺癌发病率比不吸烟者高10倍至20倍,喉癌发病率高6至10倍,冠心病发病率高2至3倍,循环系统发病率高3倍,气管类发病率高2至8倍.

单项选择题
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Shelly Nielsen sees students fall asleep in class at least twice a week. “When I see teens asleep in my class, I wonder if I am really that boring”, said Nielsen, a teacher. “I also wonder why they are so tired.” Neilson first tried to wake up sleeping students quietly. If the snoozing (呼噜声) continues, she may call a student’s parents to find out how much sleep the students is getting at night and why.

According to a research, teens need at least nine hours of sleep to function properly during the day. And more than 90 percent of teens say they are sleeping less than that each night.

Forgetting homework, yawning in class, losing concentration --- these are the signs of a sleep-deprived (被剥夺睡眠的)student, said Dr. Carl Lawyer, a specialist. “The big problem is the social demand for homework, video games and friends. Teens don’t understand how important sleep is.”

Rebecca Lucas, another teacher agrees. “Teens are busy,” she said, noting many activities most teens are involved in during the day force them to get home pretty late.” When I see teens sleeping in my class, I feel sad, like they are not sleeping enough,” she said. “I also feel frustrated because I have so much to teach in such a short amount of time and teens sleeping in the class slows me down.”

Not sleeping the needed number of hours can affect your day very much. The effect is on school, work and driving and is very frustrating to teachers when students don’t do their best because of being so tired, Lawyer said.

Al Taylor, a teacher says sleeping is not allowed in his class. “When I see a teen sleeping in my class, I feel bad that they didn’t get enough sleep but they need to correct the issue at home,” Taylor said. “I’ve raised teenage boys myself. Teenagers like to wait to the last minute to do their homework so they often stay up late trying to finish it.”

72. What does Shelly first do when she finds students sleeping in class?

A. She wakes them up with no punishment.

B. She blames herself for giving a boring lesson.

C. She asks them to stand outside.

D. She reports it to their parents.

73. Students always feel tired and sleep in class because they __________.

A. have to stay up late to do their homework.

B. are attracted by many activities.

C. are not interested in the lessons

D. are too busy to have enough sleep

74. From the last paragraph, we can infer that Al Taylor __________.

A. can easily lose his temper

B. was a father of teenage boys

C. has no sympathy for sleeping students

D. finds a good way of giving teens more sleep

75. What is the main idea of the passage?

A. Why sleep is important

B. Why teens are so tired

C. How students get enough sleep

D. How teachers manage sleeping students