1. —I left my handbag on the train, but luckily someone gave it to a railway official.
— How unbelievable to get it back! I mean, someone it.
A. will have stolen B. might have stolen C. should have stolen D. must have stolen
解析：本题考查情态动词。句意：“我把包忘在车上了，幸运的是，失而复得了”。“很难相信会有这种事发生，我的意思是，很有可能是会被别人偷走的。” will have stolen是将来完成时，表示到将来某个时间，某件事一定会发生，显然不符合语境; should have stolen表示“本该最某事”，也不符合意思; must have stolen表示“一定做了某事”，显然错误。这里应该选用might have stolen表示说话者觉得包落在火车上，很有可能是会被别人偷走的。所以正确答案为B。
答案：B
