Respuesta:
I was tired.
Everything was all right.
Betty was in bed.
Mary was too young.
You were in Canada.
The door was open.
This was my house.
We were good pupils.
Betsy and Martha were at school.
These were my teachers.
Explicación:
La conjugación was corresponde a los pronombres I, he, she, it. (singular)
La conjugación were corresponde a los pronombres you, we, they. (plural)
