Auxiliary be
From Teflpedia
Auxiliary be is the English verb be used as a primary auxiliary verb.
Auxiliary be is used with active voice in forms with the progressive aspect; the present progressive and past progressive. It is also used in all passive forms. And it is also used with modal verbs.
- I am watching TV (present progressive)
- I was watching TV (past progressive)
- I will be watching TV (modal + present progressive)
See also auxiliary do and auxiliary have.