可以举一些反例：If we mess up friend with business, there might be a great possibility of impairng the harmony relationship between you and your friends, because business is kinda official while friend is more emotional. 或者还可以列举公私分明的好处：Identifying clearly between friend and business can help you to succuss in business indeed. Everybody should have principles in mind in order to distinguish bad from good. 是自己想出来的, 水平有限, 希望对你有帮助.
