한국어 잘 못 해요. 아버지는 한국분인데 저랑 얘기할 때 한국어 안 써요. I don't like when non-native answer to that kind of question, but since you got no reply, I gave a shot. (I change "My father speaks korean" by "My father is korean" ; also "never speaks to me in Korean" by "when he talks with me, he doesn't use Korean")