An allergy is a strong reaction to a substance. Many things can cause allergies.

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An allergy is a strong reaction to a substance. Many things can cause allergies. The most common cause is pollen (花粉), which is usually produced by trees in the spring, grasses in the summer and weeds in the fall, as part of their reproductive process.
Other causes include organisms, chemicals, plants and dead skin particles from dogs and cats can also cause allergic reactions. So can insect stings and some food.
The most common kind of allergic reactions is itchy (痒的) , watery eyes and a blocked or watery nose. Allergies can also cause red, itchy skin. Some reactions can be life-threatening, for example, when breathing passages become blocked.
It is not always easy to avoid allergies. Drugs may offer an effective treatment. Another treatment used in some cases is called immunotherapy. A patient is injected with small amounts of the allergy-causing substance. The idea is that larger and larger amounts are given over time until the patient develops resistance in his body.
In the United States, experts estimate that up to 8% of young children have food allergies. Every year these allergies cause about 30,000 cases with severe reactions that require immediate treatment. It can result in breathing trouble and in some cases death. It is said that about 100 to 200 people will die. It is said that most of the reactions are caused by peanuts and tree nuts like walnuts.
People can also be allergic to medicines. The American Academy of Allergy, Asthma and Immunology says about 10％ of bad reactions to commonly used medicines are allergic. In other words, a person’s immune system overreacts and produces an allergic reaction. The most common reactions include skin rashes, itching, breathing problems and swelling in areas such as the face.
小题1:Allergies seldom occur in winter because ________.

A．plants don’t usually flower in cold weather

B．people usually wear thick clothes

C．pollen is active below freezing point

D．the weather is too cold for viruses

小题2:What will happen if one’s breathing passages get blocked?

A．It is nothing serious.	B．One’s life is at risk.
C．One has to be sent to hospital.	D．One is sure to breathe easily.

小题3:According to immunotherapy, the patient is supposed to________.

A．take some medicines to produce antibodies

B．have immediate operations

C．be given the allergy-causing substance until the patient develops resistance

D．be exposed to enough allergy-causing substances

小题4:The best title would be _______.

A．The ABCs of Allergies	B．The Cause of Allergies
C．The Treatment of Allergies	D．The Prevention of Allergies

答案

小题1:A
小题2:B
小题3:C
小题4:A

解析

试题分析：本文叙述了过敏的有关知识，人们在夏天、春天或秋天由于对花粉、花、或草过敏而导致皮肤瘙痒，流泪、红肿等症状。人们必须吃一些过敏的药来抵制这种过敏。当出现呼吸道堵塞而导致呼吸困难时，人的生命就处于危险之中，病人必须去就医。
小题1:推理判断题。根据The most common cause is pollen (花粉), which is usually produced by trees in the spring, grasses in the summer and weeds in the fall, as part of their reproductive process.因为人们对于花粉过敏在冬天由于天冷，植物不开花，故选A。
小题2:细节理解题。根据Some reactions can be life-threatening, for example, when breathing passages become blocked.当呼吸通道被堵时，会对人们的生命造成威胁，所以人的生命就处于危险中，故选B。
小题3:细节理解题。根据The idea is that larger and larger amounts are given over time until the patient develops resistance in his body.应该给病人一些过敏的药，直到他抵制过敏，故选C。
小题4:标题归纳题。纵观全文可知介绍了过敏的基础知识，故选A。
点评：细节事实理解题主要考查考生对文章中某一些特定细节或文章的重要实事的理解能力。它一般包括直接理解题和语义理解题两种。直接理解题的答案与原文直接挂钩，从阅读材料中可以找到。这种题难度低，只要学生读懂文章，就能得分，属于低层次题。而语义理解题须将题目信息与原文相关信息进行语义上的转换才能得出结论。这类题目要求考生能理解原文中某个短语或句子的含义，从而找到与答案意思相同的词语和句子。