OG9 vs PREP26

在比较10版OG第9题和PREP26的时候发现了两道相似的题目。

9. Astronomers at the Palomar Observatory have discovered a distant supernova explosion, one that they believe is a type previously unknown to science.
                    

(A) 
                    that they believe is
                    

(B) 
                    that they believe it to be
                    

(C) 
                    they believe that it is of 
                    

(D) 
                    they believe that is

(E)  
                    they believe to be of        
                    (E)

26. The electronics company has unveiled what it claims to be the world’s smallest network digital camcorder, the length of which is that of a handheld computer, and it weighs less than 11 ounces.

A.  
                to be the world’s smallest network digital camcorder, the length of which is that of a handheld computer, and it weighs

B.  
                to be the smallest network digital camcorder in the world, which is as long as a handheld computer, weighing

C.   is the smallest network digital camcorder in the world, which is as long as a handheld computer, and it weighs

D.  is the world’s smallest network digital camcorder, which is as long as a handheld computer and weighs

E.  
                is the world’s smallest network digital camcorder, the length of which is that of a handheld computer, weighing (D)

这里一个是one they believe to be...结构，一个是用what it claims is 结构，由于what 可以理解为the thing that,因此这两个结构是相似的，可以放在一起比较。我的问题是，

1)  PREP26 对于A的解释是“unveiled后面的从句没有谓语what应该做claims后面的成分"这个解释是不是欠妥当呢，因为
                如果还原原句的话，应该是 it claims what to be...怎么是没有谓语呢？当然A后面的错误决定了它不是正确选项。

2）claim/believe + is/ to be概念上有什么不同， OG9解释说‘the infini­tive to be is more appropriate than the limited present-tense is in referring to an event that occurred long ago but has been discovered only recently’不知道有什么出处。（对这个问题查过以前的讨论好像没有什么头绪啊）

3） PREP26 what it claims is 中claims 后is前的这个宾语从句为什么不加that.

4) 
                如果不考虑believe is/to be的区别，OG 9的D选项改成 they believe that i s of 还是they believe is of 比较正确？

不好意思问了这么多可能很幼稚的问题，
                没办法英语基础不是很好，很多基本问题都没弄清楚，见笑拉～

谢谢rio的解答

不过第二题还是想澄清一下，你的意思是说

what it claims to be这种说法不对么,必须是 what (it claims) is ?

帮你顶 我也困惑

我第一次做的时候凭语感和你一样 认为 claims to be 很顺口,

多看几遍好象知道那么回事但说不清楚,

而且下次碰到这样的题还是不能长记性

我乱讲下, A项:unveiled之后的部分都作为其宾语, 宾语从句套了主语从句, what i claims是主语从句 用is做谓语,   to be 不定式不能做谓语成分, 但是it到底指代什么呢? 呼唤牛牛! 

复习到这道题，踢一脚，顺便说说我的看法，希望牛牛指正！！

首先，这道题的考点不在what it claims to be还是is上，而是后边的is as long as...and weighs上，这种并列在prep里经常出现，是热门考点现在；

第二，这里what it claims to be和what it claims is都对，当然我觉得还是to be好，因为unveiled在前，已经决定了后边要跟一个宾语，我觉得这不是从句，后边接to be是修饰what的；但正确答案是加is，我觉得完全是为了迷惑，让我们不知道是选B还是D，总之，我就被迷惑啦。。

LS MM，这里it是指the electronics company，所以C里的it就不对了。。

google上搜到的结果

1、Samsung Electronics has unveiled what it claims
        are its quietest ever hard drives.

2、HP
        has unveiled what it claims to be its fastest blade server offering to date.

3、A Worcestershire-based glass firm has unveiled what it claims
        is a unique range of office furniture.

4、Australian retail technology vendor Beonic has unveiled what it claims is a world-first system to improve customer service。

5、Panasonic has unveiled what it claims is the world's first Blu-ray Disc recorders that can play back BD-Video discs (ie movies sold on Blu-Ray discs, which is not as easy as might be expected.

确实to be和is结构都有，是否说明两者确实都正确。

这两个题目的结构是不一样的

第一个是believe to be的结构，就考这个；第二个的it claims做插入成分，就像rio讲的is是跟what的，不是跟claim。类似用这种插入成分的题目GWD后面几套里面有好几个，可以比较着看。

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