Hundreds of years ago, life was much harder than it is today．People didn’t have modern machines．There was no modern medicine, either．
Life today has brought new problems．One of the biggest is pollution． Water pollution has made our rivers and lakes dirty． It kills our fish and polluted our drinking water． Noise pollution makes us talk louder and become angry more easily．Air pollution is the most serious kind of pollution．It’s bad for all the living things in the world．
Cars, planes and factories all polluted air so thick that it is like a quilt （被子）over a city．This kind of quilt is called smog（烟雾）．
Many countries are making rules to fight against pollution．Factories must now clean their water before it flows（流走）away, they mustn’t put dirty smoke into the air．
We need to do many other things．We can put waste things in the dustbin（垃圾桶）and not throw（扔） it on the ground．We can go to work by bus or with our friends in the same car．If there are fewer people driving, there will be less pollution．
Rules are not enough．Every person must help to fight against pollution．
（ ）1． Hundreds of years ago, life was much harder than it is today because
A． there weren’t any modern machines B． there was no modern medicine
C． there were not many people D． both A and B
（ ）2． What’s the biggest problem in today’s life?
A． Water pollution B．Air pollution C．Noise D．Pollution
（ ）3． The most serious kind of pollution is ．
A． noise pollution B． air pollution C． water pollution D．all of the above
（ ）4． Factories must clean their water away．
A． before they flow B． when they flow C． after it flows D．before it flows
（ ）5． From the passage we know that ．
A． a few years ago, there was no smog at all
B． today people don’t have to talk to each other in a loud voice
C． we can drink water from the polluted rivers and lakes
D． people are making rules in order to fight against pollution