If you want a bowl of milk, look at the empty bowl and then your human. The same goes for cat food. Gaze adoringly into the human's eyes and then at the empty food bowl. If you have practiced this skill effectively, then that bowl will be filled and overflowing in no time flat. They just don't learn as fast as cats.
Felines are excellent at mastering languages.
A personable woman named Ruth visited the kindly vet, since she had heard of an older cat who needed a good home. Now she had never had a cat before, but had moved into an apartment building which allowed cats, but not dogs. She was new to the world of cats, so I had my work cut out for me. When Ruth arrived at the vet's she was introduced to the older cat she had planned to adopt. Since she knew that older cats were harder to place, she decided to go that route rather than take home kitties, which are eminently adoptable, especially if they are cute.