These are my books. 这些是我的书。(指示代词作主语) Who is absent today?今天谁不在?(疑问代词作主语) Is anything wrong with your umbrella?你的伞有毛病吗? (不定代词作主语) 3.Eating too much is bad for your health. 吃得太多对你的健康有害。(动名词短语作主语) Taking a walk is much better than staying at home. 散步比待在家里要好得多。(动名词短语作主语) 4.To see is to believe.眼见为实。(动词不定式作主语) It will take him 3 hours to go to the station on foot.他步行去车站需要3个 小时。(It作形式主语,动词不定式短语作真正的主语)