It's wrong to be bitter and jealous toward others.
George's friend got an A in a Math test, but he failed the test.
George wants to comment on his friend's grade.
George congratulates his friend for getting a good grade in the test.
George criticizes that his friend got a good grade because of good luck.
His friend thanks George and gives valuable advice to him on how to get a better grade in the test.
His friend feels offended and turns away from him.