Fred looked a bit confused for a moment, before he realized that Helga had been speaking of the car that passed her. "That car? Yeah, you need to watch out for those. They're harmless as long as you don't find yourself in front of one." Fred only thought cars to be harmless because he found himself to be somewhat intrigued by them. It appeared as though he had inherited some of his father's fascination with muggle things.
"My name is Fred Weasley, by the way." He wasn't certain who this woman was, but he had a feeling that she wasn't from the same time as himself. While he didn't have too much experience with cars (aside from helping Ron and George drive one to rescue Harry Potter) he at least knew of them, and recognized them on the street.
"...do you mind if I ask what year it is, where you're from?"