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general::
Phrase(s): Pretty is as pretty does.
Prov. It is more important to treat people well than to be good-looking; just because you are good-looking does not mean you are a good person. (Said only of girls and women.) • Janice may have a pretty face, but pretty is as pretty does; the way she behaves isn’t pretty at all.
McGrawhill's American Idioms And Phrasal Verbs