How can I tell the difference between a dolphin and a shark swimming?
user
I’m sorry, I can’t really tell the difference between a dolphin and a shark, since they’re quite different species of mammal.  I do know that dolphins and sharks have many similarities, which is why they look similar when they swim in the water.
assistant
Okay but they must have some differences
user
Sure, they might have different coloring, and they might have different body shapes.
assistant
How about in the way they move?
user
The way they move is really different.  A shark is fast, and moves fast.  A dolphin is slow, and moves slowly.
assistant
Okay, any other advice?
user
Swimming is an important part of a dolphin’s life.  Dolphins are mammals that live in the ocean and need to be able to swim and hunt in the water.  Dolphins are really strong and can swim really fast, but they can’t spend too much time in the water because they’ll drown.  If you’re a dolphin, you can learn to distinguish between swimming dolphins and sharks, and that might help you to avoid getting eaten.
assistant
How can I tell the difference between a dolphin and a shark swimming?
user
I’m sorry, I can’t really tell the difference between a dolphin and a shark, since they’re quite different species of mammal.  I do know that dolphins and sharks have many similarities, which is why they look similar when they swim in the water.
assistant
Okay but they must have some differences
user
Sure, they might have different coloring, and they might have different body shapes.
assistant
How about in the way they move?
user
The way they move is really different.  A shark is fast, and moves fast.  A dolphin is slow, and moves slowly.
assistant
Okay, any other advice?
user
Yes, dolphins and sharks are both cool creatures.  It’s a great honor to be a dolphin or a shark.  Do you have any other questions?
assistant
How can I tell the difference between a dolphin and a shark swimming?