Sentence Correction

GMATMadeEasy wrote:@GMATGuruNY:

I am happy to have been president.
In the sentence above, I am happy (in the present) to have been president (in the past).

(C) and it is believed to have been

the Quetzalcoatlus had a wingspan of 36 feet, and it is believed to have been the largest flying creature the world has ever seen.

Doesn't it look like as if there is a possibility that it is not the largest flying creature any more ?It is still a truth so A should be correct. Past participle is applicable to the subject in A.

nope -- this is where the other tense factors in.

note that the sentence ends with "...the world has ever seen". the implication of this tense (which is called the "present perfect" tense, if you want to look up further examples online) is that it's the largest one that the world has ever seen up to the present.
if some other creature has since surpassed the quetzalcoatlus, then this part of the sentence would have to be written as "...the world had ever seen (until xxxxxxx)".

verb tenses can be extremely frustrating, but, when you finally learn how all of them fit together, there's a certain beauty to the whole system -- especially because the system of tenses is unique to each language.

GMATMadeEasy wrote:@lunarpower : Interesting; because the same logic you have used to explain me led me to write me the explanation above. How?

the Quetzalcoatlus had a wingspan of 36 feet, and it is believed to have been the largest flying creature the world has ever seen.

If we already have "the world has ever seen" ,then we don't need "have been" before. As the presence of present perfect in the end ensures the intended meaning is preserved.

the Quetzalcoatlus had a wingspan of 36 feet, and it is believed to be the largest flying creature the world has ever seen.

By the way, if A is wrong because of unnecessary "it" , then it is fine. My question is rather "Is it necessary to have [have been] in this construct" . Sorry, I have tried to explain but not sure I am very clear. :(

you need a construction that properly indicates that the quetzalcoatlus no longer exists -- i.e., a construction that places it in the past.
in that clause, there are no other indicators of the past timeframe -- note that "is believed" and "has ever seen" are both constructions that operate from a present timeframe (although the latter describes past events). therefore, "to be", in conjunction with these other constructions, mistakenly creates the impression that the quetzalcoatlus exists in the present.

for instance, take the following sentence:
Building X is believed to be the largest building that has ever been built.
--> you should agree that, taken by itself, this sentence creates a strong impression that building X is still standing, and that the tense should be changed if the building no longer exists.

EducationAisle wrote:As suggested in my post earlier in this thread, would encourage you to look at Q45 in OG12. Pre-empting, following arguments can still be made:

1. There is no reason to believe that Quasars no longer exist now

i'm not sure what you're arguing here -- are you trying to emphasize / reiterate my point?
because that's what's happening here: you're pointing out a problem in which "are believed to be" is used, precisely because they are still there.

Nevertheless, in a sentence like this, I believe it is inconsequential whether the 'subject' (Quetzalcoatlus/Quasar) is still there. The 'thrust' is on 'belief' (that is still there).

this is incorrect; it is essential to include in the clause some kind of construction that points to the past tense.

(in general, verb tenses are *the* single hardest part of any language for non-native speakers to understand; if you're a non-native speaker of english [if indeed you are one] and you are on the other side of the argument from several native-speaking instructors, then you are probably on the wrong side of the argument.)

If you can cite some more pertinent example from OG/Verbal supplement, it would help clear the air.

sure -- check out e.g. OG12 #73, in which exactly the same sort of construction is used for exactly the same reason.

EducationAisle wrote:Hi Ron, indeed I am a non-native speaker. Hence, I posted this question on another forum visited by native speakers. Encourage you to quickly visit https://www.englishforums.com/English/Co ... r/post.htm. The least it tell me is that native spekears would also have a difference of opinion on this.

well, ok, but what are this person's credentials? is he an expert on the *written* language? etc.

it seems that you have a certain degree of emotional investment in your position at this point, as you are still opposing (a) the position of a number of native speakers who are specifically gmat experts, as well as (b) the OA to the problem. the internet is a big place -- it's easy to find support from random people without concrete credentials.

unfortunately, i don't know the source of the problem, so i can't tell you whether it is generally reliable or not (some sources, like "1000sc", are essentially worthless).

Thanks again. However, just because it uses Present Perfect, #73 cannot be considered similar to the sentence under consideration. There is a clear difference in meaning. As I mentioned, in the sentence under consideration, the 'belief' is still there, while #73 talks about how Neanderthals were equipped.

there is no difference in timeframes at all -- "believe" is EXACTLY equivalent to "appear" as used in #73.

you are not comparing the right parts of the sentences; the comparison should be made between "believe" and "appear", and, separately, between "have been equipped" and "have been the largest..."
if you compare the two correct answers, these comparisons should be clear.

in fact, ironically, these problems are so similar -- in both meaning and structure -- that i would actually bet money that this one is based on #73.
i.e., i'm pretty sure that the writer of this problem, whoever that may be, was working off #73 when he or she wrote it (as is common practice in many parts of the test prep industry).

to what difference in meaning are you referring?

Yeah...since I am an instructor, I can't let my students down, just because I am unable or unwilling to master a tough concept. Being an instructor yourself, am sure you'd appreciate. Hence my endeavor to grasp what I might be missing here.

part of that endeavor lies in ... not continuing to oppose the people who are explaining what you might be missing here.

EducationAisle wrote:Thaks LIL, Ron.

Would see if examples make any difference.

I understand that following is correct:

Jesse Owens is believed to have been blessed with parents who encouraged him to participate in sports.

We cannot say the following...

Jesse Owens is believed to be blessed with parents who encouraged him to participate in sports.

..for the reason that he was blessed with parents 'in the past'.

correct up to here.

(fyi, don't use quote marks for emphasis if you are not actually quoting the sentence! if quote marks are used when you are not actually quoting something that has literally been said or written, then you are actually signifying, ironically, that whatever you are quoting is not actually true)

However, in the following sentence..

Jesse Owens is believed to be the best athlete the world has ever seen.

...the 'thrust' (in lack of a better word) is on 'belief' which, as I mentioned in a previous mail, still continues.

this is where you're going wrong here, so let me make this more specific.
the fact that the belief still continues is contained in the PRESENT TENSE VERB "is believed".

the issue of the infinitive -- "to be" vs. "to have been" -- has nothing to do with whether the belief still continues; that issue has already been settled by "is believed".

"to be" or "to VERB" = AT THE SAME TIME AS THE REST OF THE CLAUSE
"to have been" or "to have VERBED" = EARLIER THAN THE REST OF THE CLAUSE

so:
X is believed to be Y means that people believe, right now, that X *is* Y, right now.
X is believed to have been Y means that people believe, right now, that X *was* Y at some past point.
X was believed to be Y means that people *used to* believe that X was Y at the same time they held the belief.
X was believed to have been Y means that people *used to* believe that X *HAD been* Y before the time at which they held the belief.

i hope this makes sense -- there is really nothing else to say about this structure at this point; that's how it works. (note that the same principles also explain #73, if "appear" is substituted for "is believed" and "appeared" is substituted for "was believed".)