The sun warms the earth, which makes it possible for plants to grow. (作宾语)

　　太阳晒热大地, 从而使植物得以生长。

　　He opened the window for the fresh air to come in. (作状语)

　　他打开窗子好让新鲜空气进来。

　　There is a lot of work for you to do. (定语)

　　你有很多工作要做。

　　Had better have students discover some rules by themselves before explaining to them as follows.

　　3. Consolidate the infinitive and make sure that students can use different types of infinitive.

　　Ask students to finish Activities 2 and 3 individually, and then check their answers with their partners. Then ask some students to share their answers with the whole class.

　　（Show the following on the screen. ）

　　1. I'm traveling during a sandstorm. It's dangerous.

　　It's dangerous to_____________ .

　　2. Experts hope that they will learn more about the movement of thunderstorms.

　　Experts hope to_____________ .

　　3. We were told, "Don't leave the house. "

　　We were told not_____________ .

　　4. The men need to complete the work on the house by the end of the week.

　　The work on the house needs to_____________ .

　　5. It seems that most houses have been destroyed by the storm.

　　Most houses seem to_____________ .

　　Ask students to answer the questions.

　　Suggested answers:

　　1. travel during a sandstorm

　　2. learn more about the movement of thunderstorms

　　3. to leave the house

　　4. be completed by the end of the week

　　5. to have been destroyed by the storm

　　（Show the following on the screen. ）

　　1. It's frightening_____________ (walk)in the road in a sandstorm. I hope I reach home soon.

　　2. Experts hope_____________ (learn)more about the movement of thunderstorms.

　　3. I'd like_____________ (tell)about the situation before now.

　　4. The work needs_____________ (complete)by the end of the week.

　　5. My father was out of the city when the sandstorm came. He was very glad_____________ (miss)it.

　　6. The building has_____________ (finish)by the end of this year.

　　7._____________ (see)a real sandstorm was very frightening.

　　Suggested answers:

　　1. to walk　2. to learn　3. to be told　4. to be completed　5. to have missed　6. to be finished　7. To see

From the above exercises try to master their meanings and can use them in sentences correctly and properly.