Where in Pygmalion do we find specific examples of courage?

One
character in who demonstrates courage is Eliza. When we first meet her,
she is scolding a gentleman (Freddie) for bumping into her--something someone of her class
should probably not do.  Then she stands toe-to-toe with Higgins in their conversation about. 
She does begin to wail several times, of course, but she does...