Question

【题目】All flights______ because of the air traffic control, the passengers had to wait in the hall.

A. were put off B. having put off

C. having been put off D. have been put off

Answer 1

【答案】C

【解析】考查独立主格结构。all flights 是put off“推迟”。前后两个分句间没有连词，故不是两个简单句，前半句只能用分词形式，因此不选D。put off的逻辑主语不是the passengers而是all flights,构成“主语+分词”结构，这是独立主格结构。Put off与all flights构成被动关系，且先发生于主句谓语had用having been done 形式：having been put off。句意：因为航空管制，所有的航班被推迟，乘客不得不在大厅等候。故选C。