"عِنْد سيث تي شيرْت."
Translation:Seth has a t-shirt.
Not really. Regardless of how we write t-shirt in Arabic, our ability of learning Arabic grammar remains materially unchanged...
I mean there are real important grammar points to understand and discuss if required; rather than how to write t-shirt. If we change it to shirt, skirt, or trousers, it doesn't change the basic Arabic sentence structure.