GMATGuruNY wrote:

ngk4mba3236 wrote:gmatguru,
is the following an error in C:
by using acoustical signals, not [by] using olfactory ones, and by attracting --> the [RED] portion is dropped,resulting into an incorrect parallelism grammatically.

This line of reasoning is valid.

GMATGuruNY wrote:The structure in the OA is as follows:
CLAUSE + NO COMMA + using.
In this structure, using may serve to refer to the preceding SUBJECT if the intended meaning is crystal clear.

Rule:
A VERBing modifier cannot serve to modify a third-person pronoun serving as the object of preposition (to him, for her, from them, by it, etc.) .

ngk4mba3236 wrote:

GMATGuruNY wrote:The structure in the OA is as follows:
CLAUSE + NO COMMA + using.
In this structure, using may serve to refer to the preceding SUBJECT if the intended meaning is crystal clear.

Rule:
A VERBing modifier cannot serve to modify a third-person pronoun serving as the object of preposition (to him, for her, from them, by it, etc.) .

is the above rule true for any Object pronoun on GMAT ?

and will a VERBing modifier without a COMMA before it ever serve to modify a possessive pronoun on GMAT SC ?

ngk4mba3236 wrote:i think, these are valid errors in option A:

1. by the use of acoustical signals, but not [by] olfactory ones --> the [RED] portion is dropped,resulting into an incorrect parallelism grammatically.

2. use of "they" is redundant and breaks parallelism.

ngk4mba3236 wrote:similarly, option E is wrong for the following reason as well (apart from the reason you mentioned earlier in this thread) :

using acoustical signals, but not [using] olfactory ones, and attracting --> the [RED] portion is dropped, resulting into an incorrect parallelism grammatically.

GMATGuruNY wrote:

2. use of "they" is redundant and breaks parallelism.

This line of reasoning seems invalid.
In A, the forms connected by and -- male whistling moths call, they use -- are parallel.
The OA to SC52 in the OG12 employs a similar structure:
Josephine Baker made Paris her home, and she remained in France during the Second World War.


Dear Guru,
i have doubt your reasoning. I depnded on your post below:
https://www.beatthegmat.com/og12-two-qs- ... 81625.html

According to the post, the OA to SC52 in the OG12

In the OA for the first SC, giving remained its own subject (she) serves a purpose: it separates the second action (she remained in France) from the first (Josephine Baker made Paris her home). This separation is needed because the introductory modifier (long before it was fashionable) refers only to the first action.

However, I find the question under discussion in this post is similar to the the other sentence in your post:

Joan of Arc, a young Frenchwoman who claimed to be divinely inspired, turned the tide of English victories in her country by liberating the city of Orleans and persuaded Charles VII of France to claim his throne.

In the second SC, the she in answer choice A serves no purpose, making D (the OA) the better answer choice.

So I believe that the structure in second example resembles the structure of the question under under discussion. So 'she' should be removed.

What do I miss?

Thanks

Mo2men wrote:So I believe that the structure in second example resembles the structure of the question under under discussion.

What do I miss?

Thanks

GMATGuruNY wrote:

ngk4mba3236 wrote:i think, these are valid errors in option A:

1. by the use of acoustical signals, but not [by] olfactory ones --> the [RED] portion is dropped,resulting into an incorrect parallelism grammatically.

This line of reasoning seems invalid.
In A, the forms connected by but not -- acoustical signals, olfactory ones -- are parallel.
It is not necessary that the preposition of be repeated..

GMATGuruNY wrote:

ngk4mba3236 wrote:similarly, option E is wrong for the following reason as well (apart from the reason you mentioned earlier in this thread) :

using acoustical signals, but not [using] olfactory ones, and attracting --> the [RED] portion is dropped, resulting into an incorrect parallelism grammatically.

This line of reasoning seems invalid.
The forms connected by but not -- acoustical signals, olfactory ones -- are parallel.

ngk4mba3236 wrote:isn't the phrase -- "BY olfactory ones" -- required here for a better parallelism ?

getting confused here because earlier in this thread we've discussed that similar parallelism error holds true for option C!

if such parallelism error constitutes an error in C, then could you please clarify that why E will NOT be wrong here for the reason I stated above ?

Scientists believe that unlike the males of most species of moth, the male whistling moths of Nambung, Australia, call female moths to them by the use of acoustical signals, but not olfactory ones, and they attract their mates during the day, rather than at night.
(A) by the use of acoustical signals, but not olfactory ones, and they attract
(B) by the use of acoustical signals instead of using olfactory ones, and attracting
(C) by using acoustical signals, not using olfactory ones, and by attracting
(D) using acoustical signals, rather than olfactory ones, and attract
(E) using acoustical signals, but not olfactory ones, and attracting

GMATGuruNY wrote: C: Male moths call female moths to them by using acoustical signals, not using olfactory ones.
Here, the function of the red portion is not crystal clear.
Interpretation 2:
Male moths call female moths to them using olfactory ones.
Here, the red portion is an ADJECTIVE serving to describe male moths.

GMATGuruNY wrote:When a by-modifier serves to express HOW the preceding subject performs an action, the preferrred construction is BY + VERBing.
Incorrect: John earned a fortune by wise investments.
Correct: John earned a fortune by investing wisely.

GMATGuruNY wrote: C: Male whistling moths call female moths to them...by attracting their mates.
E: Male whistling moths call female moths to them...attracting their mates.
These options convey a nonsensical meaning that is analogous to the following:
Men at parties call women to them by attracting their wives.
Eliminate C and E.

ngk4mba3236 wrote:

GMATGuruNY wrote: C: Male moths call female moths to them by using acoustical signals, not using olfactory ones.
Here, the function of the red portion is not crystal clear.
Interpretation 2:
Male moths call female moths to them using olfactory ones.
Here, the red portion is an ADJECTIVE serving to describe male moths.

I guess, there should be NOT before the above RED portion of Interpretation 2. right ?

ngk4mba3236 wrote:

GMATGuruNY wrote:When a by-modifier serves to express HOW the preceding subject performs an action, the preferrred construction is BY + VERBing.
Incorrect: John earned a fortune by wise investments.
Correct: John earned a fortune by investing wisely.

so, is this preference always considered in GMAT SC whenever we need to express HOW the preceding subject performs an action ?

and any example when BY + NOT VERBing construction will be used in GMAT ?

GMATGuruNY wrote: C: Male whistling moths call female moths to them...by attracting their mates.
E: Male whistling moths call female moths to them...attracting their mates.
These options convey a nonsensical meaning that is analogous to the following:
Men at parties call women to them by attracting their wives.
Eliminate C and E.

this error applies to B as well, I think! right ?

as for E, could you please shed some light on the entities in the parallel list ?