2、They have done things they ought ___ A. not to do B. not to be done C. not to have done D. not having done 3、I' m sorry I couldn't get in touch with him before he left, I ___ him earlier. A. had a telephone B. have phoned C. should have...
④"be to do"的2种用法: a) 表示“按计划、安排即将发生某事或打算做某事”。 例:She is to be seen in the lab on Monday. 星期一你准会在实验室见到她。 b) 该做或不该做的事情(语气...
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