What is the difference between "It's a piece of cake" and "ain't nothing but a chicken wing"? Is the last sentence "ain't no thing but a chicken wing"? Somehow I understand it. I guess the first one means 「朝飯前(=before grabbing food in the morning)」, and the second one does 「屁の河童(=a kappa of poot)」in Japanese. A kappa is half human and half turtle, who is some soft of monster founded in old Japanese folktales. In this case, I recognize we Japanese use the "kappa" as a slang word instead of that "a chicken wing" in English. I'm not sure if my perspective is proper though...