If fish evolved into amphibians how come there are still fish?
I know you were joking, but how do you answer that question? It's a common one from theists.
If chickens come from eggs, how come there are still eggs?
Some fish with adaptations that would make them more suitable for land dwelling yet rather water dependent lifestyles. The fish with those adaptations migrated onto land, and through a long period of evolution, including many dead ends, became what we call today amphibians. Those fish without such adaptions remained in the water as fish, following a more marine based evolution.
Also, if all dog breeds are descended from wolves, how are there still wolves? I guess the problem we deal with in these types of situations is not how to just provide people with the correct information, but how to prevent people from making such horrible comparisons and asking such obviously stupid questions to begin with. To me, dog breeds are a great example of evolution in a way, in that you don't really see a whole lot of wild poodles or terriers, yet they exist as pets. Because at some point a long time ago, people starting domesticating wolves, and select for those features within the species that were most desirable to them. Further experimentation with breeding led to a greater diversity, until you see the variety of dog breeds present today.
I admit that my analysis of evolution as presented here may not be perfect, but I think it is probably a lot better of a representation than most theists would put forth.