请教大全748、849题：不定式

dandan74

我提几点，看看行不行：
1。降低时态的priority,先看其它的语法点和句子的意思。
2。首先要考虑这个动作是不是需要强调完成的结果，其次完成时表示在一个动作之前的动作，可以用和相关的动词比较来判断。

748题强调"已经“recover而不是recover这个动作，to recover不能和好的表示"已经”（主要判据），而且recover 在known之前。（辅助判据）
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

taste再known之后，但是known已经是完成时，所以用have know不好，更重要的事和taste同时发生的request用了requesting 而不是having requested. （个人认为是致命错误）
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

19。明显强调“已经”，也就是born的结果（主要判据）。
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

再来一例：明显强调“已经”enter了，to enter表达了时间概念模糊
325. Geologists believe that the Bering land bridge, over which human beings are thought to have first entered the Americans, disappeared about 14,000 years ago when massive glaciers melted and caused the sea level to rise several hundred feet worldwide.
(A) are thought to have first entered
(B) were thought first to enter
(C) were thought at first to enter
(D) are thought of as first entering
(E) were thought to first enter

本来用have bother和bother都可以，但是was reported决定了只能用to bother.
Balzac drank more than fifty cups of coffee a day and died of caffeine poisoning; furthermore, caffeine did not seem to bother Samuel Johnson, the great writer and lexicographer, who was reported to have drunk twenty-five cups of tea at one sitting.
(A) furthermore, caffeine did not seem to bother
(B) however, caffeine did not seem to bother
(C) however, caffeine did not seem to have bothered
(D) furthermore, caffeine did not seem to have bothered
(E) in addition, caffeine did not seem to bother

gemj

再来一个：
734.    The domesticated camel, which some scholars date around the twelfth century B.C., was the key to the development of the spice trade in the ancient world.
(A) The domesticated camel, which some scholars date
(B) The domesticated camel, which some scholars having thought to occur
(C) Domesticating the camel, dated by some scholars at
(D) The domestication of the camel, thought by some scholars to have occurred
(E) The camel’s domestication, dated by some scholars to have been
ANSWER：D

cappuccino

1. GMAT 中, THINK, ALLEGE, KNOW ... 后面的动词不定式,常用HAVE DONE.
2. 上面 的狂犬病的离子,用HAVE DONE 表示这个事实,延续到现在
3. ONCE + HAVE DONE, 表示持续的动作

allaneli

晕

solome

734的关键是不是平行对应呢，我是这样判断的，没有考虑不定式。
The domestication of the camel... was the key to ...

不定式被gemj问的越来越糊涂了，热烈期盼有人给出指导

tianwan

彻底晕倒！

[此贴子已经被作者于2004-4-12 15:33:21编辑过]

freedownload

大家是不是没有看见to前后都是完成式的例子？

dashasha

同晕，同晕，请牛牛们指导。到底有定论了没有？喜欢钻研的mariezhu mm呢？

mariezhu

还没有找到什么理论的依据，不过看了大家的讨论和提供的例子，我想其实刚开始的一位大牛所说的应该是正确的，以be found to do为例，（个人认为这个结构已经imply了do的内容发生在found之前，因为只有已经做了某事，才可能be found）可以是

have been found to do sth 个人觉得时态重心在have been found，弱化了do的发生时间，只强调do这一事件，已发现某某如何如何

be found to have done sth时态重心在后面的have done sth, 强调do已经发生，即发现某某已如何如何

但是不能是have been found to have done sth，这种形式表面上看似乎想搞清find和do的发生时间先后，但是其实毫无必要，而且实际上造成了更大的混淆，此外看起来也非常的awkward。

另外大家在考虑的时候肯定还要看看前后的未划线部分有没有提供选择的线索。实际上sc一个选项的错误往往是不唯一的，即使在不定式上迟疑不决，也往往可以通过其它的考点排除干扰项。

个人看法，共同探讨

入画

感觉题目中有强调事件已完成的意味，就要用完成时：

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 had miscarriages or to have borne children with heart defects  

The fear of rabies is well founded: few people are known to have recovered from the disease once the clinical symptoms have appeared

  Geologists believe that the Bering land bridge, over which human beings are thought to have first entered  

  The domestication of the camel, thought by some scholars to have occurred around the twelfth century B.C., was the key to the development of the spice trade in the ancient world.

如果题目中的事件可以延续，一直发生都不会有逻辑错误，就直接用to do

The Western world’s love affair with chocolate is well-documented:few people have been known to taste it.

Balzac drank more than fifty cups of coffee a day and died of caffeine poisoning;however, caffeine did not seem to bother.