Question

¿Como se utiliza was/were?

Answer 1

El verbo ser/estar en inglés es el siguiente: 

To be(infinitivo) was/were(pasado) been(participio) being(gerundio) 

Was se usa para la 1ª persona del singular y las 3ª del singular. 
I -> I was beautiful 
He-> He was tall 
She -> She was fool 

Were se usa para la 2º persona del singular y todas las personas del plural. 
you -> You were beautiful 
we -> We were tall 
they -> they were fool

Answer 2

verbo en ingles ser o estar pero en pasado significa fui o estuve. 

I was Yo fui o estuve 
You were Tu fuiste o estuviste