单选题 Before she could shout "look ______" to the old man, he was run ______ by a car coining from his left.
A. back, on B. out, over C. up, down D. ahead, at

【正确答案】 B
【答案解析】[解析] 本题是说在她喊出“小心”之前，老人就被车撞倒了。look out的意思是“小心”； run down的意思是“撞倒，撞翻”，因此B项为正确答案。