Hadnt it been for his help,we wouldnt have finished the work

peter finished his work ,we didnot help him 合并成一句 __thier help,we finished the work in time.A:because B:for C: (Had it not been) for your help ,we'd never have been able t had it not been for their help,we wouldn't have succeeded为什么 we have already finished the work该被动 We have finished all the lessons.It is time for us to r___ t Without his help I finished the work（同义句）___ ___his help,I f Have you been finished your work? peter finished his work.we didn`t help him合并成一句 if it hadnt rained that day we would have fhnirhed it becaus We'll have it when all the work is finished.为什么主句用将来时而宾语从句却用 Have you finished the work?