Be family (am,is are,was,were,will be)

Subjects        present    past                 future

I                         Am          was                 will be

We                     Are         were                will be

You                    Are        were                will be

You                   Are        were                will be

They                Are          were               will be

He                    Is             was                will be

She                 Is              was               will be

It                     Is                was             will be

In be family so many uses are there I will explain one usage that is about noun

Every sentence has a structure so I will explain with that only

NOUN

Subject +am/is/are+noun- positive form

Subject +am/is/are+not+noun- negative form

Am/is/are+subject +noun- question form

Am/is/are+subject+not+noun- negative question form

Example:

I am a teacher 

I am not a teacher 

Are you a teacher?

Aren't you a teacher?

He is my friend 

He is not my friend

Is he your/my friend?

Isn't he your/my friend? 

She is my sister 

She isn't my sister

Is she your/my sister?

Isn't she your/my sister?

They are my relatives 

They're not my relatives 

Are they your relatives?

Aren't they your relatives?