WHAT IS THE VERB TO BE?
The verb to be is used to describe that state of existence of people, things, places, and ideas. The verb to be means to exist (I am here), to occur (The meeting is Tuesday), or to have the characteristics of something (She was a quiet child).
It is the most common verb in English, partly because of its additional uses in grammar: to be verbs can be auxiliary verbs that help create other tenses or linking verbs that help describe the subject of a sentence.
The principal use of the simple present is to refer to an action or event that takes place habitually, but with the verb "to be" the simple present tense also refers to a present or general state, whether temporary, permanent, or habitual.
The verb to be in the simple present can be also used to refer to something true at the present moment.
Uses
We use the simple past tense of the verb to be for any state to describe a person or situation in the past.
Use was for I, he, she and it.
Use were for you, we and they.
SIMPLE FUTURE
Uses
The simple future with verb to be is used to talk about states that will probrably happen in the future.
E.g. I will be a doctor.