the are after which makes things clear..its the compounds..

Manojks,

The relative pronoun WHICH refers to the noun directly before it and not to the entire clause. In the question you posted, since manual research comes directly before WHICH, WHICH modifies manual research.

Hope this helps.

kooladitya01 wrote:the are after which makes things clear..its the compounds..

but "which" should modify the noun placed just before it. am i right?

if "which" modifies manual research then "which are more likely to become marketable pharmaceutical products" is wrong because "marketable pharmeceutical products" refers to compounds. please clarify.

MelissaLim wrote:Manojks,

The relative pronoun WHICH refers to the noun directly before it and not to the entire clause. In the question you posted, since manual research comes directly before WHICH, WHICH modifies manual research.

Hope this helps.

compounds (that are....),which are...;

Here "compounds" is modified by essential 'that' clause and then by a non essential 'which' clause;
also 'which are' can't refer to manual research; It looks fine to me but I am not an expert.

manojks wrote:in addition to being more expensive than manual research,machine-based research often identifies compounds that are of lower quality than those identified by manual research, which are more likely to become marketable pharmaceutical products.

Q-i am confused whether "which" modifies manual research or compounds?

in addition to being more expensive than manual research,machine-based research often identifies compounds that are of lower quality than those identified by manual research, which are more likely to become marketable pharmaceutical products.

If "which" is modifying compounds, the intention of the sentence becomes "Compounds that are of lower quality are more likely to become marketable pharmaceutical products". "Which" is a relative pronoun and can be replaced by the noun it refers to, if it really refers to "compounds" in this case.

As per the rule, "which" modifies the immediate preceding noun, and in this case should modify Manual Research logically. Continuation of the sentence might not be true or needs to be constructed in another manner. If the "which" exists then the continuation should logically belong to Manual Research or if the other part "are more likely to become marketable pharmaceutical products" should be true, then the sentence should be something like

in addition to being more expensive than manual research,machine-based research often identifies lower quality compounds,which are more likely to become marketable pharmaceutical products, than those identified by manual research . - this looks clear and crisp.

Please provide the original sentence for more analysis.

Feel free to critique.

Thanks,
HK

xtremecoder007,

You have raised valid point regarding the meaning of the sentence if which clause is modifying compounds directly. However, I am not convinced that which should modify market-research.

After reading the sentence, I think which clause is modifying those[(compounds) identified my manual reasearch];

i.e. those compounds that are identified by manual research;

This is a tricky one! Let's think about the logic of the sentence. We're comparing two sets of compounds: the compounds identified by machine-based research (lower quality) and the compounds identified by manual research (more likely to become marketable pharmaceutical products). In the sentence, the second set of compounds (manual research) is referred to by the plural pronoun "those." Since it's THOSE compounds that are more likely to become marketable, it's THOSE compounds that the adjective clause is logically describing, so you're absolutely right, GMATVerbal, that the adjective clause is modifying the pronoun "those."

Now, what about the structure? Remember that a relative pronoun must be as close as possible to the noun OR NOUN IDEA it modifies. A noun idea is a noun and modifier that exist as a unit and cannot be interrupted. In this case, we have the noun idea "those identified by manual research." A relative pronoun immediately following this noun idea could modify EITHER the noun right before it, "research," OR the subject noun of the idea, "those." We need to use logic and agreement to determine the appropriate modification. Here's a similar example:

The cluster of islands, which are constantly at war with one another, is in the Pacific Ocean.
The cluster of islands, which is larger than any other cluster, is in the Pacific Ocean.

Both of these sentences are correct -- the noun idea is "cluster of islands."

Hope that helps!