It was rude you to stare at the foreigner when he passed by just now.
A. of
B. for
C. with
D. to
网友回答
(答案→)A. of
B. for
C. with
D. to
解析：考查介词：这是it做形式主语的句型：It is +adj+for/of+sb +to do sth,如果形容词是指人，用of，如果形容词指不定式的动作，用介词for，浙江沿海的形容词是rude是指人，所以介词是of，句意：你刚刚看着外国人走过的时候真是不礼貌。选A。