Question - Identify and explain the error

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Question - Identify and explain the error

by pingu » Sat Apr 23, 2011 7:02 am
Triceratops, a dinosaur existing around 68 to 65 million years ago and thus one of the latest species to appear before the suggested extinction event of dinosaurs occurring 65 million years ago, thought to have had two horns on its forehead and one on the bridge of its nose.

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by Brent@GMATPrepNow » Sat Apr 23, 2011 7:19 am
pingu wrote:Triceratops, a dinosaur existing around 68 to 65 million years ago and thus one of the latest species to appear before the suggested extinction event of dinosaurs occurring 65 million years ago, thought to have had two horns on its forehead and one on the bridge of its nose.
The error here is that there is no verb to accompany the subject (Triceratops).
a dinosaur existing around 68 to 65 million years ago and thus one of the latest species to appear before the suggested extinction event of dinosaurs occurring 65 million years ago is a phrase that modifies Triceratops.
Similarly, thought to have had two horns on its forehead and one on the bridge of its nose is also a phrase that modifies Triceratops.
So, we have a subject that isn't "doing" anything. For a complete sentence, we need a subject and we need a verb associated with that subject (the subject must "do" the verb).
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by jaymw » Sat Apr 23, 2011 7:21 am
Hey pingu,

can you please post questions in full, i.e. with all answer choices and source?

Sometimes it is not the case that an answer choice in an SC problem is technically wrong, sometimes it's just the case that some other answer choice is more concise and thus better.

The sentence you posted, however, does contain a clear error. As it is written, it would suggest that the dinosaur itself thought that it had horns, which, of course, is non-sensical.

Something along the lines of "is thought to have had..." would be a better fit.

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by pingu » Sat Apr 23, 2011 7:45 am
For a beginner, I think it is more important initially to identify the errors in the original sentence.
jaymw wrote:Hey pingu,

can you please post questions in full, i.e. with all answer choices and source?

Sometimes it is not the case that an answer choice in an SC problem is technically wrong, sometimes it's just the case that some other answer choice is more concise and thus better.

The sentence you posted, however, does contain a clear error. As it is written, it would suggest that the dinosaur itself thought that it had horns, which, of course, is non-sensical.

Something along the lines of "is thought to have had..." would be a better fit.

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by jaymw » Sat Apr 23, 2011 6:09 pm
pingu, sure it is important for everyone (not only "beginners") to understand why an answer choice is wrong. But, as I said, sometimes answer choice A is not wrong, but is just not the most concise way of expressing an idea. Therefore, it is usually greatly helpful to compare the answer choices against each other.

Any test taker should start with this comparison after reading the prompt. Finding out where the answer choices differ helps you in terms of spotting the error. This technique is sometimes called the 2/3 split.

Apart from that, posting the source helps people ignore potential problems from CATs they are about to do.

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by HSPA » Sat Apr 23, 2011 7:10 pm
1)Tricyclops = "a" dinosour = singular
2)Here past perfect is not requried - "was" should be among option
3)a thought = present activity = is

Now the original option says "Triceratops thought to have" == It is not dinosaur who thinks but some archiologists. So original option is out.

Using 1 and 3:
IMO : Triceratops is thought to have two horns on its forehead.

But still the verb "is" vague in here and I can only judge based on options [B/C/D/E]
Now since as per your request I have provided you the initial error post the options..please
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by atulmangal » Sat Apr 23, 2011 7:47 pm
HSPA wrote: 2)Here past perfect is not requried - "was" should be among option
@HSPA

Please indicate where is Past perfect tense used in the sentence...

Have Had ----> Present perfect tense

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by HSPA » Sat Apr 23, 2011 8:17 pm
atulmangal wrote:
HSPA wrote: 2)Here past perfect is not requried - "was" should be among option
@HSPA

Please indicate where is Past perfect tense used in the sentence...

Have Had ----> Present perfect tense
Yup agreed.. No wonder I was not able to use option 2 of mine in my IMO. So what is your answer atul and also put down your notes on "have had" I will do a copy paste to my dB
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by atulmangal » Sat Apr 23, 2011 8:38 pm
HSPA wrote: put down your notes on "have had" I will do a copy paste to my dB
A special note on the usage of HAD

HAD alone is always Simple Past.

Had + 3rd form of any verb is Past Perfect.

The usage of HAD HAD:

He HAD HAD a great life before the calamity struck.

Here, the second HAD is correct... Imagine it as

He HAD ENJOYED a great life before the calamity struck.

So here the second HAD ≡ any other verb (enjoyed, for example).

Usage of HAS HAD / HAVE HAD

He has had a great life ≡ He has enjoyed a great life.

So here HAD ≡ any other verb (enjoyed, for example).

Similarly, the sentence:

I have had a great life ≡ I have enjoyed a great life.

So here HAD ≡ any other verb (enjoyed, for example).

Hope this help

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by pingu » Sun Apr 24, 2011 9:14 am
I don't have the answer options for this question. In future I will post answer choices, if the question has them.

Brent rightly said -The error here is that there is no verb to accompany the subject (Triceratops). we have a subject that isn't "doing" anything. For a complete sentence, we need a subject and we need a verb associated with that subject (the subject must "do" the verb).

An addition to what Brent has said - Only the first verb in a sentence should be conjugated i.e. rightly indicate the tense.

Thought is not associated with Triceratops and is not Conjugated. So introduce a conjugated verb i.e. is thought (First verb). Also the next verb - To Have is an infinitive( non-conjugated). Thus complying to the above rule.

Correct answer is:
Triceratops, a dinosaur existing around 68 to 65 million years ago and thus one of the latest species to appear before the suggested extinction event of dinosaurs occurring 65 million years ago, is thought to have had two horns on its forehead and one on the bridge of its nose.