英语动名词作为主语时，通常表示一个持续的动作或状态，而不是一个具体的行为。动名词作为主语时，谓语动词通常用第三人称单数形式。以下是一些使用动名词作为主语的英语句子示例：

1. Reading books is my favorite hobby.

2. Playing sports regularly keeps you healthy.

3. Reading is one of my favorite hobbies.

4. Swimming is good exercise for your whole body.

5. Listening to music helps me relax.

6. Doing morning exercises is good for our health.

7. Planting trees is a very effective way to absorb carbon.

8. Attending classes on time is a way of showing respect to your teachers.

9. Traveling is my favorite hobby.

10. Exchanging your ideas with other participants regularly can deepen your understanding of the drama.

11. Keeping in contact with each other is definitely important.

12. Smoking is prohibited here.

13. Climbing mountains is really fun.

14. Doing much exercise is good for your health.

15. Reading is an art.

16. Don't put your bike on the playground.

17. It is useless to learn without practice.

18. Walking after dinner is good for your health.

19. It felt funny to watch myself on TV.

20. It is no use arguing with Bill because he will never change his mind.

这些例句展示了动名词在句子中作为主语的各种用法，希望对你有所帮助。