There are five infinitives in English: to be, to do, to have, to say, and to go. Each one has a different function and purpose.
To be is used as a verb indicating existence or occurrence, to indicate identity or character, or to indicate a permanent state or condition.
To do is used as a verb indicating action or instinctive reaction. Its purpose is to add energy or liveliness to a sentence.
To have is used as a verb indicating possession, ownership, or creation. It can also be used to express existence or occurrence.
To say is used as a verb indicating communication. It is the act of uttering words or sounds.
To go is used as a verb indicating motion or movement. It expresses the idea of travelling from one place to another.
