11、Recently, ______________ has become the focus of the society, and in this way.. People swarm to ______________.
12、______________ has been playing an increasingly important role in our day-to-day life. It has brought us a lot of benefits but created some serious problems as well.
13、Man is now facing a big problem-______________, which is becoming more and more serious. First, ______________ second, ______________.
14、Nowadays more and more people are beginning to be aware of the seriousness of ______________.
15、It is only during the last years that man has become generally aware that ______________.
16、There is an old saying, ______________. It's the experience of our forefathers, however, it is correct in many cases ever today.
17、The English proverb says, ______________. This is quite true because ______________.
18、______________ is now______________, and at the same time ______________. These two factors have caused ______________. Then what shall we do to solve ______________ in the face of such a situation.
19、One of our ancient philosophers said, ______________. Chinese people have always been holding this idea to be one of their standards of morality.
20、One of the great early writers said that ______________. If this is true, the present situation should make us ponder over ______________.
