Am, is, are, was, were, and will be are different forms of the verb to be.
Am, is, and are are the present forms:
- I am a little bit crazy.
- He/ She is just as crazy as me.
- It is the worst day of my life.
- You/ We/ They are not crazy at all.
Was and were are the past forms:
- I/ He/ She was so happy to see you.
- It was the best day of my life.
- You/ They were happy for me.
You can use will be to talk about the future:
- I/You/He/She/It/They will be there tomorrow.
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