请问下面单选怎么做,为什么,Mever before ___ see such a terribel var accident on the road.A.i have B.have i C.i did D.did i

请问下面单选怎么做,为什么,Mever before ___ see such a terribel var accident on the road.A.i have B.have i C.i did D.did i 这些单选怎么做? 这几个单选怎么做 请问下面的英语单选怎么解释,为什么,If she wants to stay thin,she must make a ____ in her diet.A.chance B.turn C.run D.go 请问这道题怎么做?为什么这么做? order单怎么做 请问下面几道图形题怎么做? 请问下面这道题用直线方程的方法怎么做? 请问下面四道计算怎么做?谢谢了 请问下面的结构力学题怎么做, 请问下面这题怎么做呀,我做的在下面, 请问这题怎么做,公式?为什么? 英语单选,选D,请问A为什么不行? 英语翻译你今天做了几单买卖.请问这句话该怎么翻译 竹字头下面一个单怎么读拼音 下面这道题怎么做? 请问下面的英语单选怎么选,为什么多谢啦!______ for your help, we'd never have been able to get over the difficulties.A. If it were not B. Had it not been C. Had it not D. If we had not been 禁止做什么的英语单为什么