People have smoked cigarettes for a long time now. The tobacco which is used to make cigarettes was first grown in what is now part of the United States. Christopher Columbus, who discovered America, saw the Indians smoking. Soon the dried leaves were transported to Europe . In the late 1800s, the Turks made cigarettes popular.
Cigarette smoke contains at least two harmful substances, tar and nicotine. Tar, which forms as the tobacco burns, damages the lungs and therefore affects breathing. Nicotine, which is found in the leaves, causes the heart to beat faster and increases the breathing rate. Nicotine in large can kill a person by stopping a person’s breathing muscles. Smokers usually take in small amounts that the body can quickly break down.
Nicotine can make new smokers feel dizzy(头晕) or sick to their stomachs. The heart rate for young smokers increases 2 to 3 beats per minute. Nicotine also lowers skin temperature and reduces blood flow in the legs and feet. It plays an important role in increasing smokers’ risk of heart disease and stroke.
Smoking cigarettes is dangerous. Cigarette smoking was the cause of lung cancer and several other deadly diseases.
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Tobacco first appeared in_________.
A.Asia | B.Africa |
C.Europe | D.America |
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What is the main purpose of the first paragraph?
A.To tell us the bad effects caused by smoking cigarettes |
B.To introduce the history of smoking |
C.To let us know what the cigarettes are made from |
D.To tell the readers that Columbus found the Indians smoking |
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._________doesn’t make one’s heart beat as usual.
A.Tar | B.Nicotine |
C.Lung disease | D.Leave |
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The following effects are caused by Nicotine EXCEPT that________.
A.It can make new smokers feel dizzy or sick to their stomachs |
B.It lowers skin temperature |
C.It causes the heart to beat less fast |
D.Nicotine will probably kill a person if a smoker takes in too much of it. |
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What’s the main idea of this passage?
A.Where did cigarettes come from? |
B.The effect of smoking on your body. |
C.How to smoke is healthy? |
D.Who is the first smoker? |