For those who might be interested, I have a really nifty little interactive tool at toontitan.com that allows you to view the various mouth sprites needed for a character. Just click button at the top of the article on Mouth sprites. Once its open you can click the frames and it will show you a representation of the mouths to use.

Check it out at: https://toontitan.com/kb/g2-character-mouth-chart.html



I often find myself using it when developing new characters, i just open it on the side as I draw the mouths for the new character. 

Ibis Fernandez   |   (available for hire)
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Professional Animator, Filmmaker | Creator of the highest quality (modular) G2 rigs for cartoon animator and developer of Toon Titan and Puppet Producer 
Author of Flash Animation and Cartooning: A Creative Guide
>>> be sure to check out http://toontitan.com for professional grade assets, templates, and custom tools for Cartoon Animator and more.