Resposta:
Use Was para I (eu), he (ele), she (ela) e it e Were para you (você), we (nós), you (vocês) e they (eles/elas).
Portanto...
I was crossing the red light when accident took place.
Sheena (She) was at home yesterday.
You were so happy yesterday.
They were working on their chemistry project.
She was in USA last month.
Did She say what she was doing.
They were in front of the Garden.
We were at school last Sunday.
Where were they playing.
The boys were climbing on the tree.
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Mark was here.
This dog was funny.
I was busy.
You were very lucky.
The winter was cold.
They weren't tired.
We were hungry.
This book wasn't boring.
Explicação:
As formas negativas were+not fica weren't. Assim como was+not fica wasn't.
