We’re surrounded by chemistry in everyday life. Sometimes it is easy to see, like when your science teacher does a big experiment in class. At other times, it can be pretty hard to see everyday chemistry at work, but nearly everything you touch or use has some element of chemistry in it.
Something as simple as toothpaste contains at least three chemicals, if not more. It is the mixture of them and its chemical reaction that keeps your teeth clean. Other things you use every day are created by chemistry, such as hair products, shampoo and soap. Adding detergent (洗涤剂) to water involves chemistry. Without chemistry, we would never have known that we need soap to get the oil out of clothes or skin. Chemistry not only helps us make products for use, but it also helps us understand the world around us. Chemistry helps us understand what the ozone layer (臭氧层) is and how it protects us. Chemistry also gives us sunscreen to protect us from the sun. Thanks to chemistry, we know bleach (漂白剂) can’t be mixed with vinegar(醋), because it can produce poisonous gas.Without chemistry, we wouldn’t have fireworks displays on important days.
Chemistry plays a big role in food preparation. Cooking food causes it to go through a chemical change. That is why cooked food often tastes different from raw food. Baking is a great example of chemistry. Too much or too little of any ingredient（成分，尤指烹饪） makes a difference to the result of baking, for example, the dough (面团) won’t rise or the cake will be flat.
Chemistry isn’t something that just lives in a lab; it’s something that you meet hundreds of times every day. Knowing how chemistry works will give you a greater understanding of the science behind some of the simplest-looking things.
小题1:What’s the main idea of Paragraph 1?
A．Chemistry is easy to see around us.
B．Sometimes chemistry is hard to see around us.
C．How a science teacher does a big experiment.
D．Few things in everyday life contain chemistry.小题2:The following actions are about chemistry EXCEPT _____.
A．cleaning teeth with toothpaste
B．washing hair with hair products
C．using soap to get the oil out of clothes
D．washing your face with water小题3:The underlined word “poisonous” in Paragraph 3 means _____.
A．harmful
B．healthy
C．fresh
D．pleasant小题4:Which one is TRUE according to Paragraph 4?
A．One can’t find chemistry when cooking food.
B．Chemistry plays an important part in food mak-ing.
C．That dough rises is nothing to do with chemistry.
D．A flat cake is the result of too many ingredients.小题5:Which of the following would be the best title for the text?
A．Chemistry Around the House
B．Chemistry in Science
C．Chemistry for Dinner
D．Chemistry in everyday life
小题1:B
小题2:D
小题3:A
小题4:B
小题5:D
题目分析：本文叙述了在人们的日常生活中化学无时不在无处不在，文中举了一些例子，了解化学能够帮助我们理解我们的生活中的一些自然现象。我们的生活离不开化学。
小题1:这是概括大意题。根据At other times, it can be pretty hard to see everyday chemistry at work,这是本段的中心句，故选B。
小题2:这是细节理解题。根据Something as simple as toothpaste contains at least three chemicals 和Other things you use every day are created by chemistry, such as hair products, shampoo and soap.水里没有化学物质，故选D。
小题3:这是词义猜测题。根据Thanks to chemistry, we know bleach (漂白剂) can’t be mixed with vinegar(醋), because it can produce poisonous gas 两者不能想混说明混合在一起会发生反应而产生对身体不利的东西，故选A。
小题4:这是细节理解题。根据Chemistry plays a big role in food preparation 故选B。
小题5:这是标题归纳题。根据We’re surrounded by chemistry in everyday life.从短文的首句及整篇短文来看，本文叙述的是日常生活中的化学，故选D。
点评：概括大意这种题型的实质是让考生给每段文字“命”一个小标题。而要“命”出这个标题来就必须确定每段文字的主题思想。如何确定文章和主题思想？考虑一下人们的写作和逻辑思维过程，这个问题就容易回答了。