求大神帮忙找出这些英语句子的主语分别都是什么

求大神帮忙找出这些英语句子的主语分别都是什么
1. Rubbish, however, is only part of the problem of polluting our planet.
2. The use of pesticides and fertilizers produces cheap grain and vegetables.
3. Second, attending college or university can change our life.
4. It is extremely doubtful whether we would equally enjoy reading about ourselves.
5. Dancing proved to be more than the dish could bear.
6. The third reason for attending a college is to increase knowledge.
7. Why people tolerate a four-hour journey each day for living in the country is beyond me.
8. With the knowledge learned in a university, we will have a deep understanding with our society.
9. The people who want a good job have to study hard and at least graduate with a high education.
10. The people who graduate from college seem more confident in our community.
11. Competition of our days has become more and more drastic, and even a very simple job or low position will attract hundreds of candidates to apply for it.