题目

___________ a fine day, Shenzhou VI will be launched on time according to its planned time. A. Being   B. It being  C. To be  D. It is 答案：B 解析: 本题考查独立主格结构。前一分句和后一分句在逻辑上存在因果关系，可以排除答案D。因为前面的分词的逻辑主语不可能是后面一个分句的逻辑主语，故前一分句要有一个逻辑主语it表示天气。27、You know he is not going to let us leave early if we ___ get the work done. A. can't                B. may not                   C. shouldn't                 D. mustn't