I have a question, you may think it is ridiculous but is it kind of confusing for me.
when i say "she is judy", what is subject and what is object here? are there any objects?
She is judy.
Subject + Copula + Complement
There is no object. The complement (a noun) refers back to the subject. The complement could alternatively be an adjective: Judy is smart.
An object, on the other hand, is a seperate entity which is in some way effected by the action described by the verb.
I am not a teacher.