This is the 1368th most frequent Turkish word.
sizin
"Your" or "yours" (plural or formal singular).
Here, 'sizin' indicates possession, showing that the house belongs to you.
Sizin eviniz çok güzel.
Your house is very beautiful.
In this sentence, 'sizinle' means 'with you' by combining 'sizin' with the suffix '-le' indicating a company.
Sizinle sinemaya gitmek istiyorum.
I want to go to the cinema with you.
Here, 'sizin' emphasizes respect by addressing the listener(s) formally and showing possession of the opinion.