You're just being overly pedantic. They hold their breath, fully submerge, control their buoyancy, and propel themselves through water. Also known as swimming.
National Geographic
https://www.nationalgeographic.com/animals/mammals/facts/hip...
> Hippos cannot swim or breathe underwater, and unlike most mammals they are so dense that they cannot float. Instead, they walk or run along the bottom of the riverbed. Because their eyes and nostrils are located on the top of their heads, they can still see and breathe while underwater. When totally submerged, the ears and nostrils shut tight to keep the water out, and hippos can hold their breath for five minutes.
San Diego Zoo
https://animals.sandiegozoo.org/animals/hippo
> Yet despite all these adaptations for life in the water, hippos can't swim—they can't even float! Their bodies are far too dense to float, so they move around by pushing off from the bottom of the river or simply walking along the riverbed in a slow-motion gallop, lightly touching the bottom with their toes, which are slightly webbed, like aquatic ballet dancers.
Also echoed by Cincinnati Zoo and I'm certain many other experts.
But yes, it is maybe pedantic to define swimming!
However, even if you'd be kind to this LLM and say "Alright, sure, it's kinda swimming", it's still wrong in terms of being among particularly good mammal swimmers! This is just flat out wrong no matter how you look at it. They're terrible at it but have evolved to not need to be awesome at this.
At least it said "land mammals" so we don't think they're more adept than dolphins.
It's funny to see people complaining about this when this kind of analysis is very important to improving these systems. I want to remind people not to romanticize these systems or get attached to our expectations of what we think it should be doing. They are a novel computer system and we should be happy to objectively analyze their performance.
That is an inaccurate use of the word underwater. Underwater means beneath the surface. Breathing moves gases in and out of the lungs. These gases are not available in sufficient quantities beneath a liquid's surface to perform typical breathing behavior.
A better description is "while its body is submerged":
The hippo's nose, ears, and eyes are on the top of its head, and they protrude from the water while the rest of its head and its body lie beneath the surface. That way a hippo can breathe, see, and hear even while its body is submerged.
https://kids.nationalgeographic.com/animals/mammals/facts/hi...
You could be kind to Nat Geo Adults and Buckeyes and say "ok, that's mostly underwater" but its still wrong because of the way it talks about eyes. Light penetrates the surface of water and the Hippo's optical organs are not deleteriously effected by most liquid water unlike the alveoli of lungs. Thus eyes can see underwater even though a Hippo will not be able to breathe effectively.
GPT 3.5 (fails): https://flowch.ai/shared/90274999-8eaf-4046-9115-7f623264197...
GPT 4 (succeeds): https://flowch.ai/shared/73523ec6-4d1d-48a4-bb16-4e9cc01adf1...