请教大全748、849题：不定式

gemj

这两个题目是一个模子里出来的，为何选项及答案不一样？
748.    The fear of rabies is well founded: few people are known to recover from the disease after the appearance of the clinical symptoms.
(A) few people are known to recover from the disease after the appearance of the clinical symptoms
(B) few people are known to have recovered from the disease once the clinical symptoms have appeared
(C) there are few known people who have recovered from the disease once the clinical symptoms have appeared
(D) after the clinical symptoms appear, there are few known people who have recovered from the disease
(E) recovery from the disease is known for only a few people after the clinical symptoms appear

849.    The Western world’s love affair with chocolate is well-documented: few people have been known to have tasted it for the first time without requesting more.
(A) few people have been known to have tasted it
(B) few having been known to taste it
(C) it has been tasted by few people
(D) few people have been known to taste it
(E) few people having tasted it
是否印证了我当初的设想：

可以是现在知道过去如何：
are known to have recovered

也可以是过去知道当时如何：
have been known to taste

但不可以是过去知道过去如何：
have been known to have tasted

[此贴子已经被作者于2003-11-6 14:56:49编辑过]

joywzy

gemj,这两题的关键在于，不定式后的动作是否早于谓语动词，来判断是否用完成时。不用考虑其它任何因素。这题我也刚刚得到解决。

gemj

太好了，那你跟我说说你的思路？

joywzy

gemj,我试试：

T748，are known / recover ，谁先？recover先，所以are known to have recovered

T849, have been known/ taste it ，谁先？know 先。

因为tasted it for the first time without requesting more.不知我讲明白了没有啊？

joywzy

补充一点：

只有are known to have recovered / have been known to recover

not  have been known to have recovered

gemj

以下是引用joywzy在2003-11-5 23:44:00的发言：
gemj,我试试：

T748，are known / recover ，谁先？recover先，所以are known to have recovered

T849, have been known/ taste it ，谁先？know 先。

按道理说不管是TASTE还是RECOVER都应该发生在KNOWN之前，因为没有发生的事情你怎么知道呢？

我的意思是说：其实这两个句子结构是一样的，说的事虽然不同，但语法上的内核是完全一样的，结果ETS给出了两套答案。我想问的是对于这种情形的描绘为什么两种用法都没有问题？

另外，通过这两套正确答案，ETS想表达的信息是什么？

gemj

下面是我设想的一个反例，各位高手不妨就此来讨论指教一下不定式的用法：何时用完成时，何时不用？
19.    The herbicide Oryzalin was still being produced in 1979, three years after the wives of workers producing the chemical in Rensselaer, New York, were found to have borne children with heart defects or miscarriages, and none of their pregnancies was normal.
(A) to have borne children with heart defects or miscarriages, and none of their pregnancies was
(B) to have had children born with heart defects or miscarriages, and none of the pregnancies was
(C) either to have had children with heart defects or miscarriages, without any of their pregnancies being
(D) either to have had miscarriages or to have borne children with heart defects; none of the pregnancies was（D）
(E) either to have had miscarriages or children born with heart defects, without any of their pregnancies being

[此贴子已经被作者于2003-11-6 14:56:23编辑过]

joywzy

顶顶.我以为自己明白了,又被gemj问糊涂了.可能还是没大明白.

谢谢大家的帮助.

dandan74

我ye糊涂了, braveMBA, miejue,
come on!

john1388

Q: "to have tasted it for the first time without requesting more"

1. "for the first time" decides to ues "tast it" rather than " have tasted it"
2. " taste" does not mean a continuous act. " have tasted" is not accurate.

Pls read a similar sentence:
"to taste it in 1880 without requesting more"