"Wasn't" is the contraction for "was not".
wasn't
The contraction for they are is they're.
aren't
There is no contraction. The contraction we're means "we are."
There is no contraction for I was. There is a contraction for I am (I'm) and for I have (I've).
There is no contraction of we'll. It is a contraction, meaning "we will."
The contraction for they are is they're.
aren't
The grammatical contraction for "have not" is "haven't."
following gramatical rules make a sentence standard
There is no contraction for were you. There is no contraction for you were.There is a contraction for "you are" (you're).
slang
There is no contraction for "its not."There is a contraction for "it is" (it's).There is a contraction for "is not" (isn't).
Sujeto verbo y predicado
He's already IS a contraction. It is a contraction of he is.
There is no contraction. The contraction we're means "we are."
There is no contraction. There is a contraction doesn't which means "does not."
There is no contraction for I was. There is a contraction for I am (I'm) and for I have (I've).