"I do not eat the butterfly."
Translation:Non mangio la farfalla.
"no" is used as a response, as in "NO, I don't eat meat;" while "non" is used to make a verb negative, an in "I do NOT eat meat." an example of an Italian sentence with both would be "no, non mangio carne." where "no" is my response to the implied question, "mangi carne?" basically no=no and non=not.