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Specific expressions can't be described as clearly and distinctly as they can be drawn. "A picture is worth a thousand words" - unless the picture is generic.
These kinds of expressions would not be created at the model sheet stage by a designer. The designer can't anticipate every scene of a cartoon and all the emotions a character will experience. Specific expressions have to be created by either the storyboard artist, the layout man, director or animator. They are customized to the character and each specific moment within the story.
If you are working on a production where everyone has to stick to the model sheets, then your cartoon will not have specific expressions. It will have pre-designed generic expressions.
This makes most cartoons less interesting on an acting level than live action. Real people do not have a mere handful of pre-determined expressions created by someone else. They have their own unique myriad of expressions and can make them spontaneously with little effort. We cartoonists don't have it so easy. We have to imagine each expression and then figure out how to draw it - a very unnatural procedure. This might explain why it hardly ever happens.