having lost consciousness for twenty hours ,the wounded soldier____at lasta came to b came through为什么不选b

英语单项（需解释） --------in the mountains for a week ,we finally saved by local policeA ,Having lost B,Losing C ,Being lost D,Having been lost 这这边,having lost the key=lost the key么?句子是这样的：Having lost the key,the boy couldn't enter his house. The key ___,he could not enter the room.A having been lost B had been lost C having lost D losing ___(having lost/ lost)in the mountains for a week,the 2 students were finally saved .答案选的是LOST,搞不懂为什么如果是HAVING BEEN LOST可以吗？BEING LOST呢？ in the mountains for a week ,the two students were finally saved by the local policeA Having lost B lost C being lost D losing有几种大家回答的比较多的答案,having been lost ,lost,having lost ,还有,为什么不可以用being lost? __in thought ,he almost ran into the car in front of him.A losing B having lost C lost D to lost哪个对呢?losing 和having lost有什么区别呢? ____ his key, the man looked ____a. Lost; worried b.Losing; to be worriedc. Having lost; worried为何选C? Even the best writers sometimes fingd themselves ____for wordsA lose B lost Cto lose D having lost Having been 是什么时态Having been lost in the mountains for a week ,the two students were finally saved by the local police.为什么不是 have been lost lost lost lost lost lost lost lost lost. lost