单选题 July: Hello, Mr. Green. ______. Mr. Green: You're leaving so soon? When are you off? July: Early tomorrow morning.
【正确答案】 B
【答案解析】解析:本题考查告别的对话。正式而且礼貌的说法是I’ve come to say goodbye或者I’m afraid I have to go now,所以正确答案是B。