3.　　　 To hear the accident is sad.

T: Maybe you have found something different. What’s the function of “to do”?

S: As the subject of the whole sentence.

T: Great! That’s it. We can use the infinitive to work as the subject of the whole sentence. But how come these sentences “It’s + adj. + to do”? Well, do you want to have a big, long head and short legs? Maybe that will look uncomfortable. So we need our old friend “it” to help us. Thus we have all these sentences.

Then ask students to read the following aloud.

2.　 To eat vegetables is good.

1.　 To watch a movie is interesting.

1. to + v. 2. It’s + adj. + to do 3. need to do sth. 4. be to do sth.

T: We can see that the above sentences all include “to + v”. In fact they are in the same family, and they are called “infinitive”. (Write “infinitive” down and ask students to use a red pen to emphasize the infinitives). Now look at the first sentence. Can you give me more examples?

S: It’s good to eat vegetables.

S: It’s sad to hear the accident.

S: It’s nice to see you here. It’s easy to learn math. It’s right to tell the truth.

T: Excellent! Now I want to change these sentences. Look carefully, please.

Show the following.

6. The surprising thing was to hear that bad news.

Step II Explanation

First encourage students to tell the similarity between the sentences.

Show the following.

5. HongKong is a good place to buy things.

4. We need to finish our homework every day.

3. I am surprised to see you here.

2. It’s not hard to learn English.

1. It’s interesting to watch a movie.