Question

8．To extinguish （熄灭） different kinds of fires，several types of fire extinguishers have been invented．They must be ready for immediate use when fire breaks out．Most portable （手提式的） kinds operate for less than a minute，so they are useful only on small fires．The law requires ships，trains，buses and planes to carry extinguishers．
Since fuel，oxygen and heat must be present in order for fire to exist，one or more of these things must be removed or reduced to extinguish a fire．If the heat is reduced by cooling the material below a certain temperature，the fire goes out．The cooling method is the most common way to put out a fire．Water is the best cooling material because it is low in cost and easy to get．
Another method of extinguishing fire is by cutting off the oxygen．This is usually done by covering the fire with sand，steam or some other things．A blanket may be used do cover a small fire．
A third method is called separation，which includes removing the fuel，or material easy to burn，from a fire，so that it can find no fuel．
The method that is used to put out a fire depends upon the type of fire．Fires have been grouped in three classes．Fires in wood，paper，cloth and the like are called Class A fires．These materials usually help keep the fire on．Such fires can be stopped m ost readily by cooling with water．
19．If a fire breaks out on a bus，which of the follow should be ready there for you to use？C
A．Sand         B．Water        C．An extinguisher．D．A blanket．
20．To cover a small piece of burning wood with a basin in order to stop the fire is an example ofD．
A．separating the fire．
B．reducing the heat
C．removing the fuel                
D．cutting off the oxygen
21．In choosing how to put out a fire，we should firs t be clear aboutD．
A．when it breaks out               
B．where it takes place
C．how it comes about               
D．what kind it is
22．What would the author probably discuss in the paragraph that follows？C
A．Another type of extinguishers         
B．How fires break out．
C．Another class of fires            
D．How fires can be prevented．

Answer 1

分析 文章分析了不同的灭火原理和方法，提醒人们灭火时的注意事项．

解答 19．C．细节题．根据第一段最后一行The law requires（要求） ships，trains，buses and planes to carry extinguishers．可知灭火器是必备的，故选C．
20．D．推理题．和第三段内容Another method of extinguishing fire is by cutting off the oxygen．一样，这样做很明显是为了氧气，这样达到灭火的目的．故选D．
21．D．细节题．根据文章最后一段第一句The method that is used to put out a fire depends on the type of fire．可知灭火前要知道火的种类，故选D．
22．C．推理题．根据文章最后一段Fires have been grouped in three classes可知有三种火，刚刚在最后一段讲述了一种火，接下来应该是讲述另外一种火．故选C．

点评 本篇文章都是细节推理题，答题的已给选项也一般不会和短文相关词语完全相同，需要考生自己理解句子，延伸推理出题目答案，比一般细节理解题偏难．