Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are now drawing solid conclusions about how the human brain grows and how babies acquire language.
A. Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are
B. Neuroscientists, having amassed a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are
C. Neuroscientists amassing a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are
D. Neuroscientists have amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood,
E. Neuroscientists have amassed, over the past twenty years, a wealth of knowledge about the brain and its development from birth to adulthood,
答案是A,我选的是E,不是说having+done结构不能作定语吗?
作者: balabaladou7 时间: 2009-2-26 00:34
E肯定是不对的,它改变了原句的含义,句子的重心。
句子的结构是:
Neuroscientists, (插入语修饰主语)are now drawing solid conclusions about A & B。
但E却改变成:
Neuroscientists have amassed a wealth of knowledge about A & B,now drawing......
没有:having+done结构不能作定语 这样的定论。
作者: aeoluseros 时间: 2009-2-26 11:50
having done这里是做定语.
我认为having done作定语主要是会产生时间上的歧义:having done的东西是延续着、持久着(现在分词短语做定语的内在含义之一),还是已经完结。over the past twenty years时间状语的存在让这重歧义不存在,表明了已经完结,所以是可以这么用的.
open to discuss.
open to discuss.
open to discuss.
open to discuss.
open to discuss.
作者: songlovegt 时间: 2009-2-26 12:08
是不是也应该考虑主句里使用了现在进行时 Neuroscientists are now drawing 作者: aeoluseros 时间: 2009-2-27 18:04
以下是引用aeoluseros在2009-2-26 11:50:00的发言:
having done这里是做定语.
我认为having done作定语主要是会产生时间上的歧义:having done的东西是延续着、持久着(现在分词短语做定语的内在含义之一),还是已经完结。over the past twenty years时间状语的存在让这重歧义不存在,表明了已经完结,所以是可以这么用的.
open to discuss.
open to discuss.
open to discuss.
open to discuss.
open to discuss.
修正一下观点:
非限制性的having done是可以用的,但是限制性的不能用.
作者: zyitbest 时间: 2009-3-25 14:12
以下是引用aeoluseros在2009-2-27 18:04:00的发言:
修正一下观点:
非限制性的having done是可以用的,但是限制性的不能用.
为什么非限制性的having done是可以用的,但是限制性的不能用呢?
还想请问一下版主over the past twenty years的位置是否合理呢?
E. Neuroscientists have amassed, over the past twenty years, a wealth of knowledge about the brain and its development from birth to adulthood,
D now drawing 改变句子重心,主干部分变成了修饰部分。原句强调的是Neuroscientists are now drawing.
E now drawing 改变句子重心,主干部分变成了修饰部分。原句强调的是Neuroscientists are now drawing.
作者: 天蝎座1107 时间: 2009-4-18 22:16
Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are now drawing solid conclusions about how the human brain grows and how babies acquire language.
A. Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are首先要读懂句意 科学家先要amassed很多的knowledge才能够draw solid conclusions这里用having用的很好体现出了动作的先后 从逻辑意思上就可以判断出来 然后要注意看到状语 看到代词要小心
B. Neuroscientists, having amassed a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are状语位置的改变产生歧义 原先是having amassed a wealth of knowledge over the past twenty years这里的over the past twenty years是与现在完成时连用的 然而B选项改成its development from birth to adulthood over the past twenty years以为是大脑的发展从出生到成人这20多年的历史 and多余
C. Neuroscientists amassing a wealth of knowledge about the brain and its development from birth to adulthood over the past twenty years, and are状语位置的改变引起歧义 and多余 去掉的have不能体现动作的先后
D. Neuroscientists have amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood,改变句子重心
E. Neuroscientists have amassed, over the past twenty years, a wealth of knowledge about the brain and its development from birth to adulthood,改变句子重心
作者: snow13 时间: 2009-4-23 04:00 Neuroscientists, having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, are now drawing solid conclusions about how the human brain grows and how babies acquire language.
prep1-188中,A选项"having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood",你可以把这个成分理解成状语,也可以理解为定语,修饰的都是Neuroscientists这个主体或这个主体发出的动作,只要你把having看做定语和状语时,句意理解起来是一样的,那么就没有歧义问题。
而prep1-97:Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.这里面having可能修饰pollutants,也可能修饰they have introduced some 100,000 dangerous chemical pollutants整个分句,所以having产生了修饰歧义。
prep1-188中,A选项"having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood",你可以把这个成分理解成状语,也可以理解为定语,修饰的都是Neuroscientists这个主体或这个主体发出的动作,只要你把having看做定语和状语时,句意理解起来是一样的,那么就没有歧义问题。
而prep1-97:Industrialization and modern methods of insect control have improved the standard of living around the globe while at the same time they have introduced some 100,000 dangerous chemical pollutants, having gone virtually unregulated since they were developed more than 50 years ago.这里面having可能修饰pollutants,也可能修饰they have introduced some 100,000 dangerous chemical pollutants整个分句,所以having产生了修饰歧义。
The perfect participle indicates completed action. You form the perfect participle by putting the present participle having in front of the past participle.
For example:-
Having done, having finished, having read, having spoken
It can be used to form the passive voice.
For example:-
Having improved her English Pia's promotion prospects were much better.
Option E indicates that "having kept" is a completed action. So, it is not correct.作者: cptiger 时间: 2011-3-27 16:40
主语Neuroscientists后面两个逗号间插入的部分,不管是状语还是定语,都可以看成是插入语,那么把句子稍微变化一下: having amassed a wealth of knowledge over the past twenty years about the brain and its development from birth to adulthood, Neuroscientists are now drawing solid conclusions about how the human brain grows and how babies acquire language. 是不是再看,就可以看出来是做状语的。Having done结构做定语有问题,但是做状语是OK的,请NN们拍砖!作者: clairezhao2010 时间: 2011-5-25 11:45
顶9楼的解释!!作者: baibaobao 时间: 2011-11-27 15:50
是“插入语+逗号”隔开主句了作者: ainiAnnie 时间: 2012-2-3 12:48
个人觉得这里加了 逗号, having done变成了状语吧。。。。 请NN指教。作者: ptlove4ever 时间: 2012-2-3 13:24
可以把所有关于伴随状语的问题都汇聚到一块了,看来这是一大难点啊作者: Tonybonaparte 时间: 2012-2-16 01:43
摘自非谓语动词 百度百科
They went to the park,singing and talking. 他们边唱边说向公园走去。 Having done his homework,he played basket-ball. 做完作业,他开始打篮球。作者: miffyflysky 时间: 2013-5-22 19:54
(现在分词做伴随起到伴随动作和伴随结果两种功能,前者表示与主句动作同时发生,后者需要是主句动作的直接结果。当被修饰主句已经是完成时态,那么后面的现在分词本身就不可能再与主句动作发生在同一时刻,所以无法以 “伴随动作/状态”(逻主=主主,与主句谓语动作同时发生)的身份出现,只可能行使“伴随结果”(修前面整个句子)的功能)。drawing不是have amassed的直接结果,所以drawing无法做have amassed的伴随结果作者: cician 时间: 2013-11-18 13:01
为什么没有小伙伴问这个问题?DE除了句子重心的问题,OG对DE的解释里边有一条:
this sentence attempts to attach a present-tense descriptor to a present-perfect clause.
是不是这句话就不对:
Tom has succeeded, doing anything he can.
因为 ing 不能attach 现在完成时?作者: qiyouji 时间: 2014-3-7 19:27
欢迎NN分析对不对作者: LuyanWang 时间: 2018-4-8 07:41
关于 D & E
除了改变了整个句子中心以外。看comma+ving 和时态问题
从Gmatclub上看到的。
comma+ving structure modifies the preceding clauses. It says about the effect of the preceding clauses or describes how the preceding clause happened.
1. the effect,可以, 积累知识和写报告是有independent relationship的。
2. how it happened, 这个在这里不通
所以我们继续看1.the effect. have amassed 是现在完成时,表示过去的一个动作已经完成,强调对现在的影响。所以这个事情是已经完成的,整个主句的确对现在分词的部分有影响,微弱的因果关系。是满足现代分词作伴随状语的语法结构的。 comma + ving 在语法上是修饰主句的主语没问题。最终的问题出在了now.
"the main problem with D and E is "now"
doing take the tense of the main clause, "have massed" but "have massed" cannot go with "now". NOT LOGIC.
按照gmatclub 这个人的意思,ving phrase 是自动继承了主句的时态,和now代表的现在进行时冲突了。 作者: Sara.Z 时间: 2018-8-24 04:05
根据句意,重点是现在drawing solid conclusion, 所以D,E可以直接排除。C 时态丢失也算是改变句意的一种吧个人的理解, B 种后面跟着的 and are 可以直接排除答案。最后剩下的就是A。
(大多数的SC可以根据句意排除一部分答案,然后再分析语法部分来选取答案,如果觉得不太确定推荐排除法这样减少混乱,绝对错误的直接排除,剩下的就是正确答案。)