A、Infinitive has two forms: 1. to do 2. do
B、Infinitive can be used as:
1、Subject of a sentence
To do sth. is / v. + sth. It is / v. sth. to do sth.
e.g. To learn English well is not easy. It is not easy to learn English well.
To repair the car needs time and money. It needs time and money to repair the car.
To build the lab is our task.
To talk with your mouth full is not polite
To go to a first class university is my dream.
Some common sentence structures:
