I didn't manage to do it ____ you had explained how.A until B unless C when D before D为什么不对?

i didn't manage to do it_____you had explanied howAuntil Bunless Cwhen Dif i didn't manage to do it_____you had explanied howAuntil Bunless Cwhen Dif I didn't manage to do it ____ you had explained how.A until B unless C when D before D为什么不对? 一道英语单选题,I didn't manage to work out the problem( )the teacher had explained how.A.until B.unless C.when D.before为什么呢? 一道英语选择题：I didn't manage to do it ____ you had explained how.I didn't manage to do it ____ you had explained how.A untilB unlessC when D before并解释一下其他选项不选的原因. i didn't manage to do it 空格 you had explained it now ; a:until; b:when ; c : Don't stop to wait for me.I can manage to ____ youA:overtake B:overturn C:overlook D:oversee 21.We'd better hurry ______ it is getting dark.A.and B.but C.as D.unless22.I didn' t manage todo it _____ you had explained how.A.until B.unless C.when D.before23._____he comes,we won't be able to go.A.Without B.Unless C.Except D.Even24.I hurried ___ I didn't mean to, 18.--I didn't go to the movie last night.-- ________.A.I didn't,too B.I didn't,neither C.So I did D.Me,neither _______tell me about this before? Otherwise I could have helped you?I was able to manage myself.thanks anywayA How come didn`t you B How come you didn`tC How didn`t you come toD how you didn`t come to Frank didn't go to the park last Sunday.I didn't ___A.too B.also C.either D.to manage和make的区别– Did you go to see the play last night?- Unluckily,I couldn’t ________it.But I am going to see it soon.A.do B.manage C.make D.take为什么不选B? 16.They collected some valuable stamps___ they stayed in ShanghaiA.while B.as C.since D.during 麻烦帮看一下,B项为什么不正确,帮分析一下,17.I didn't manage to do it______ you had explained howA.until B.unless C.when D.before I didn't manage to do it _____you had explianed how.A.until B.unless C.when D.before为什么不能选B呢?我觉得它没有错啊,妈妈说unless前面的主句一般都没见过否定形式的,而且又有not...until.但我觉得太牵强,unless Don’t stop to wait for me.I can manage to _____ you.A：overlook B：overtake C：override D：overturn 单选题 Why'd you have lied to me I didn't know what to say ... The students didn't manage to work outthe problem ______their teacher had explained how.为什么不是unless而是until