A. ought to arrive B. ought to have arrived C. should arrive D. must arrive 参考答案:B 答案解析:ought to do sth．和should do sth．意为“应该做某事”，多用来提出劝告，如：You should (ought to) go and see Mary sometime．你应
第17题: [单项选择]He often stopped at the sound of his own steps and was afraid to look ______ his shoulder. A. over B. back C. round D. beyond 参考答案:A 答案解析:固定搭配题。look over one's shoulder意为“回头看”；look back意为“向后看，回顾”；look round意为“环视”。本句大意为：他经常被自己的脚步声吓住不敢往前走，而
