USES OF TO BE

The verb be is used in the following patterns:

1. with a noun:

My mother is a teacher.
Bill Clinton was the president of the US.

2. with an adjective:

This soup is very tasty.
The children were good.

2.1 with the -ing form to make the continuous aspect

We were walking down the street.
Everything was wet. It had been raining for hours.

2.2 with the -ed form to make the passive voice

The house was built in 1890.
The street is called Montagu Street.
This car was made in Japan.

3. with a prepositional phrase:

John and his wife are from Manchester.
The flowers are on the table.

 https://learnenglish.britishcouncil.org/es/english-grammar/verbs

https://www.youtube.com/watch?v=LH57BAO9K88