Pumas never attack ahuman being except being cornered.这句话哪里有错误,为什么错

Pumas never attack a human being except( )cornered?选项：A they are B being C that they areD when they are.为什么不能是A或C? Pumas never attack a human being except_____conered. A.that they are B when they are 为什么选B不选A Pumas never attack ahuman being except being cornered.这句话哪里有错误,为什么错 Pumas never attack a human being except( )cornered?括号里的选项：A. they areB. beingC. that they areD. when they are这是新概念中的题,给出的答案是D,不清楚为什么?请教一下大家~~! pumas never attack a human being except ___cornered.1 they are 2 being 3 that they are 4 when they are请问选择哪一个,及分别说出每个为什么对与错 是新概念英语第三册上面第一单元的.选项我只写了我觉得比较混淆的.1.People said______the puma.A.to have seen B.they had seen2._____,it immediately ran away.A.On being observedB.Having been observed3.Pumas never attack a huma 介词后面加从句一定要加that吗如题,后面是宾语从句对吗?pumas never attack a human being except_____conered.A they are B being C that they are D when they are which one is the best answer?但是when they are conered是名词性从 新概念英语3的一个选择题pumas(美洲狮）never attack a human being except__ cornered.A.they are B,being C.that they are D.when they are个人感觉B、C、D都行啊,正确答案给的是D,为什么呢? 新概念3第一课课后习题第七题Pumas never attack a human being excpt _____ conered.A they areB beingC that they areD when they are请问选哪一个?为什么?请说明为什么其他三个不能选 最好说一下except的用法 那为什 pumas never attack a human being expect _____cornered.A.they areB.beingC.that they D.when they are该选D.提问这个的很多,但我觉得还有点含糊...能说的具体些吗?还有,EXPECT后到底接不接动名词啊? Pumas never attack a human being except( )cornered?这新概念的老问题哈,可是好像谁都没说清楚.A.they areB.beingC.that they areD.when they are.except 加That从句 和when从句 这个选项中有什么区别哈,为什么一定要选D 新概念NCE3 第一课教材中的一道练习题 关于except的用法：Pumas never attack a human being except( ）cornered.A.they are B.being C.that they are D.when they are 不解.但可以肯定的是,这里的Except表示的是“除非”. 新概念3课后习题6.It immediately ran away when she saw it=_______,it immediately ran away.(a)Observing her (b)On being observed (c)Having been observed (d) On her being observed 选B,为什么不选C?7.Pumas never attack a human being except __ Pumas never attack a human being except when the are cornered帮我分析下句子成分,还有when这里引导的是状语从句吗?when 引导的如果是状语从句,那么属于哪种呢?感觉不会是时间状语吧? except的用法.（新概念）pumas never attack human being except ______ cornered.A.they areB.beingC.that they areD.when they are我觉得都对,特别是B,最简练,怎么读怎么顺.请问语法角度来说,是不是都对?回一下1楼，excep a massive heart attack 希望说下理由!1.many people stopped to listen to the music as it ___so charmingly on the piano that it attracted everyone passing by.(play)用主动还用被动?2.Pumas will not attack human beings if___undisturbed .A.left B.being left3.it was m finishing attack is a super attack中文意思同上