Recently, entomologists have discovered a number of new

Question

Recently, entomologists have discovered a number of new insect species,  most of them as common or more common than the birch aphid, a tree-dwelling insect, which live  on the bottom of oceans or within icebergs.

(A) most of them as common or more common than the birch aphid, a tree-dwelling insect, which live
 (B) most of them at least as common as the birch aphid, a tree-dwelling insect, and living
 (C) most of them at least as common as the birch aphid, a tree-dwelling insect, living
 (D) mostly at least as common as the birch aphid, a tree-dwelling insect, which live
 (E) mostly as common or more common than the birch aphid, a tree-dwelling insect, living

Hi can anyone please outline the grammatical structure of this sentence. What category does each clause belong to.

Recently (Adv. that describes noun clause) ,Entomologists (Subject), have (main verb)....what then ? where are the conjunctions ? I am a bit lost.

Recently, entomologists have discovered a number of new insect species, most of them at least as common as the birch aphid, a tree-dwelling insect, living on the bottom of oceans or within icebergs.

Btw this sentence comes from Knewton online test prep

many thanks

Sudhanshuacharya · Answer

The two parts of the sentences i.e. "most of them at least as common as the birch aphid"
and "a tree-dwelling insect" describe the "new insect species" and are considered non essential in the complete sentence. Hence there are no conjunctions.

As the scientists have already found the new species their is no ambiguity in their identification. The entire sentence can be rewritten without the above two sentences.

jamifahad · Answer

which is used to refer to the noun immediately preceding the which. Here, which will refer to insect. But insect is not living on the bottom of oceans or within icebergs, insect species is. 
Eliminate A and D.

For B, whenever we use AND after comma make sure there are two main clause before and after AND. Here since we have same subject use of comma and AND is wrong. Eliminate B.

For E, mostly as common or more common is just unidiomatic.

OA C. Also,  Living  forms an adverbial modifier.

hafgola · Answer

thanks, is there anyway for me to recognize how "most of them at least..." becomes a modifying clause, is most of the some sort of a indicator ? subordinating conjunction ?

or should I focus on the fact that there is no subject verb agreement in the clause
"most of them at least as common as the birch aphid...living on the bottom of oceans..." (modifying clause that modifies "species")

I could be tempted to think that. "most of them" is the subject, and living the main verb, is the error there that Living can´t it be the main verb because it is functioning as an Adverb (resent Participle)? -ing form

can -ing forms maybe never function as a main verb ??? (that would be a comfortable rule to remember:)

thanks

akbism · Answer

The following links may help to all those are having doubts in modifier:
1. https://www.youtube.com/watch?v=0jWmrK5BLtw
2. https://www.youtube.com/watch?v=GElSqdp5iTc
3. https://www.youtube.com/watch?v=X48hAnuxEaw
4. https://www.youtube.com/watch?v=Mo5ZXrUNBbc

daagh · Answer

The gist of the passage is that, 1. Scientists have discovered a number of new insect species (plural); these insects live in oceans or icebergs; they are at least as common as the birch aphid, a tree-dweller.

* (A) most of them as common or more common than the birch aphid, a tree-dwelling insect, which live ---  it should be ‘most of them at least as common as'

* (B) most of them at least as common as the birch aphid, a tree-dwelling insect, and living ---  Misses the symmetrical parallelism by using a noun on one side of the parallel marker ‘and’; on the other side, a participial phrase is used. 
 
* (C) most of them at least as common as the birch aphid, a tree-dwelling insect, living --  correct combination; living here modifies the new species.

* (D) mostly at least as common as the birch aphid, a tree-dwelling insect, which live --  which live is wrong modification and verb number

* (E) mostly as common or more common than the birch aphid, a tree-dwelling insect, living –  missing the idiom as common as

sunny91 · Answer

Hi Experts,
In option c, I feel there is an ambiguity regarding what living modifies. How can living modify insect species. If we remove the non-essential modifier- ,a tree-dwelling insect, then living modifies birch aphid. The sentence stands by as follows-
Recently, entomologists have discovered a number of new insect species most of them at least as common as the birch aphid living on the bottom of oceans or within icebergs.
In the comments, people , living modifies the subject(insect species) of the previous clause. But, we have the comma before living as part of non essential modifier ,a tree-dwelling insect,

sunny91 · Answer

daagh ,  GMATNinja ,  broall

In option c, I feel there is an ambiguity regarding what living modifies. How can living modify insect species. If we remove the non-essential modifier- ,a tree-dwelling insect, then living modifies birch aphid. The sentence stands by as follows-
Recently, entomologists have discovered a number of new insect species most of them at least as common as the birch aphid living on the bottom of oceans or within icebergs.
In the comments, people , living modifies the subject(insect species) of the previous clause. But, we have the comma before living as part of non essential modifier ,a tree-dwelling insect,

sayantanc2k · Answer

If two modifiers are required to be placed one after the other referring to the same antecedent, then there must be a conjunction (e.g. "and") between them. Thus if "living..." were to refer to "birch aphid", then the modifiers "a tree-dwelling insect" and "living..." would be separated by a conjunction (e.g.,"and").

Just some additional thought: If the comma before "living" were not there, then the present participle modifier "living.." would clearly refer to "insect", which in turn refers to "birch aphid".

sunny91 · Answer

Hi Sayantanc2k,
Thanks for the explanation. But, I still have the question is the OA fine?
I just want to recall my understanding from the above.
Living cant modify bird aphid. as two modifiers are required to be placed one after the other referring to the same antecedent, then there must be a conjunction (e.g. "and") between them. We have and missing. Also, even if a conjunction is there, the sentence lacks parallelism. So, living modifies a number of new insect species. 
But again, if we remove the non-essential modifier, we can read the sentence as -
Recently, entomologists have discovered a number of new insect species, most of them at least as common as the birch aphid living on the bottom of oceans or within icebergs. 
So, here the bird apchid and not a number of new insect species live on the bottom of oceans or within icebergs.

sayantanc2k · Answer

In Option C, "living" refers to "new insect species". "Living" cannot refer to "birch aphid" because of the reason I stated (and you correctly understood).

As for eliminating a non-essential modifier, you have to remove the complete non-essential modifier: "most of them at least as common as the birch aphid, a tree-dwelling insect".

"The tree-dwelling insect" is a non-essential modifier WITHIN another non-essential modifier. the structure is as follows:

Recently, entomologists have discovered a number of new insect species  living on the bottom of oceans or within icebergs.

chesstitans · Answer

daagh ,  sayantanc2k  is there are tip, or way to see that B has errors. It is difficult to me to know for sure that C is the answer.

daagh · Answer

chesstitans wrote 
 
Though belatedly, let me use chesstitans' question to reopen this thread as verbalbot wants.

The main difference between the two is the ill-timed intrusion of the conjunction 'and' in B, altering the originally intended meaning.

As per the original, the new species are a common group found in the bottoms of the oceans or the icebergs. The birch aphid is cited for the commonalty of the new insects and not for the marine habitats.

In B, the compound modifiers both refer to the aphid; after all, neither the tree nor the terrestrial insect can live under oceans or icebergs.

In C, the comma plus living is an adverbial modifier modifying the previous clause's action namely the entomologist's discovery of the new insects. This is the original intent.

VerbalBot · Answer

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Recently, entomologists have discovered a number of new

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