I'm teaching English in a non-English-speaking country where plural "s" and third-person "s" get confused a lot with no "s" at all. The dialogue in the textbook was explaining how you should respond when someone compliments you:
Mike: For example, when you have a new bag, I can say, "I like your bag."
Yuki: What should I say then?
Mike: You should say, "Thanks."
Yuki: Should I say anything else?
Mike: No. Just "Thanks."
I was asked what the "s" in "Thanks" means, but I couldn't give a straight answer. I know in the phrase "give thanks" it's a plural noun, but what about when it's used as an interjection? Why does it go from "Thank you" to "Thanks"?