1. Grammar
Infinitive

2. 动词不定式的形式 Forms of Infinitive
to do
not to do
to be done
to have done

3. 动词不定式的作用 Functions of Infinitive
主语 (subject)
宾语 (object)
表语 (predicative)
定语 (attribute)
状语 (adverbial)

4. 主语 (subject) It is kind of you to help me. （形容词修饰人，用of）
It is important for you to study English.
（形容词修饰动词不定式，用for）

5. 宾语 (object)
I found it important to study English.
（形式宾语）

6. 定语 (attribute)
sth. to eat
( eat sth.)
a room to live in
(live in a room)

7. 状语 (adverbial) I’m pleased to meet you. （原因状语)
in order to = so as to = to
（目的状语）
I went to the station only to find the train had gone.
（结果状语）

8. 表语 (predicative)
在系动词后面：
seem, be, become, look, sound, taste, smell, feel

9. One day, your doctor tells you that you have an incurable disease and may not have more than twelve months to live.
attribute

10. There did not seem much point in working on my PhD --- I did not expect to survive that long.
object

11. But in order to get married, I needed a job, and in order to get a job, I needed a PhD.
adverbial

12. He continued his exploration of the universe and traveled around the world to give lectures.
adverbial

13. Since then, Hawking has continued to seek answer to questions about the nature of the universe.
object

14. Readers were pleased and surprised to find that a scientist could write about his work in a way that ordinary people could understand.
adverbial

15. In the book, Hawking explains both what it means to be a scientist and how science works.
subject

16. Scientists look at the world and try to describe and explain what they see.
object

17. To explain what they have seen, they build a theory about the way in which things happen and the causes and effects.
adverbial

18. But if, like Hawking, they are studying something that is too large or too difficult to observe directly, they will use a model to test the theory.
adverbial

19. People who listen to Hawking’s lectures sometimes find it difficult to understand him, because his thoughts and ideas often seem as large as the universe he is trying to describe.
object

20. 带“to”的短语不一定都是动词不定式，比如according to, stick to, listen to, pay attention to, lead to, look forward to等。“to”在上述短语中作介词，后接名词，代词或动名词。

21. exercises