I searched your lessons on possessives but couldn't find this: what is the difference between "kay mwen" and "kay pa mwen"? Is there any difference in meaning or where they are used?

Grammatically,
mwen, in kay mwen, means my and is a possessive adjective.
Sa se kay mwen.
This is my house.

and,
pa mwen, in kay pa mwen, means mine and is a possessive pronoun.
Sa se kay pa mwen. (non contracted)
Sa se kay pa'm. (contracted)
This house is mine.
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