Topic–comment

So, when we talk, we say things about something, right? That something is the topic. And what we say about that topic is the comment. Let's say we're talking about a dog. The dog is the topic. And when we talk about the dog, we might say things like, "The dog is brown" or "The dog likes to play fetch." Those things we say about the dog are the comments. So, the topic is like the thing we're talking about and the comment is like what we're saying about that thing.