11. There is no denying the fact that air pollution is an extremely serious problem: the city authorities should take strong measures to deal with it. 无可否认，空气污染是一个极其严重的问题：城市当局应该采取有力措施来解决它。

　　12. An investigation shows that female workers tend to have a favorable attitude toward retirement. 一项调查显示妇女欢迎退休。

　　13. A proper part-time job does not occupy students' too much time. In fact, it is unhealthy for them to spend all of time on their study. As an old saying goes: All work and no play makes Jack a dull boy. 一份适当的业余工作并不会占用学生太多的时间，事实上，把全部的时间都用到学习上并不健康，正如那句老话：只工作，不玩耍，聪明的孩子会变傻。

　　14. Any government, which is blind to this point, may pay a heavy price. 任何政府忽视这一点都将付出巨大的代价。

　　15. Nowadays, many students always go into raptures at the mere mention of the coming life of high school or college they will begin. Unfortunately, for most young people, it is not pleasant experience on their first day on campus. 当前，一提到即将开始的学校生活，许多学生都会兴高采烈。然而，对多数年轻人来说，校园刚开始的日子并不是什么愉快的经历。

　　16. In view of the seriousness of this problem, effective measures should be taken before things get worse. 考虑到问题的严重性，在事态进一步恶化之前，必须采取有效的措施。

　　17. The majority of students believe that part-time job will provide them with more opportunities to develop their interpersonal skills, which may put them in a favorable position in the future job markets. 大部分学生相信业余工作会使他们有更多机会发展人际交往能力，而这对他们未来找工作是非常有好处的。

　　18. It is indisputable that there are millions of people who still have a miserable life and have to face the dangers of starvation and exposure. 无可争辩，现在有成千上万的人仍过着挨饿受冻的痛苦生活。

　　19. Although this view is wildly held, this is little evidence that education can be obtained at any age and at any place. 尽管这一观点被广泛接受，很少有证据表明教育能够在任何地点、任何年龄进行。

　　20. No one can deny the fact that a person's education is the most important aspect of his life. 没有人能否认：教育是人生最重要的一方面。