1. First, about education. 这句是不是完整的句子?没有主语、谓语，显然不完整。
2. Why is broad horizon important?这句是疑问句。
3. Children growing up in metropolises, chances are good that they will have a promising future. 美好未来是指哪方面，讨论的范围太过宽泛?
4. Youngsters in big cities are indirectly in possession of various educational resources.本句可作为分论点论述过程中的论据，而不是主题句。
5. A myriad of people have become well-educated; and an increasing number of people choose to foster their children in the downtown. 这句有多个主题，陈述现象而非给出个人观点。
1. Young people today are more likely to invest their time and effort on improving the world than young people in the past.
2. Students are more interested in politics today than before?
3. People will spend less time cooking and preparing food in twenty years than they do today.
4. It is easier to maintain good health nowadays than it was in the past.
5. The personal and work-related challenges that young people face today are not very different from the challenges their parents and grandparents faced in the past.