By pressing a tiny amount of nitrogen between two diamonds to a pressure of 25 milliion pounds per square inch, scientists not only were able to transform the gas into a solid, but they also created a semiconductor similar to silicon

A.
B. not only were able to transform the gas into a solid but also creating
C. were able not only to transform the gas into a solid but to create
D. were able not only to transform the gas into a solid but also creating
E. were able not only to transform the gas into a solid but they were also able to create

I am surprised by the answer. Is it acceptable to omit " also" in "not only x , but also y" structure.

Yes, it is. I don't like it much either (I remember grumbling a bit at this exact question), but it's much preferable to non-parallel structure.

Keep in mind for future questions that it IS acceptable to phrase the expression that way!

Ron Purewal,

Thanks for clarification

what was the OA ?

The OA is C, the only choice that exhibits proper parallel structure.

I agree with C, but with E is it only because it is very verbose - it seems parallel, and respect the not only - but also..

E isn't parallel.

Parallel would be "were able // not only (to X) but also (to Y)" ("were able" applies to both parts, while "to X" and "to Y" are parallel)

But this choice says "were able // not only (to X) but they were also (able to Y)"

So the opening "were able" should apply to both sets of parentheses, which would give us "were able able to Y." Which is obviously not grammatically correct. :)

Hi,
Whats wrong with the parallelism in A?
It appears to be correct? (Is the insertion of they in "but they also" a problem??)

Thanks,

if it appears to be correct, you're thinking too much.

if you have a two-part parallel construction - such as "not only ... but also" - your detection of parallelism (or lack thereof) should be COMPLETELY mechanical. just look at the words that follow the first part, and look at the words that follow the second part (and DON'T ignore any words). if they don't have the same grammatical structure, then the parallelism is faulty. end of story.

choice (a):
not only were able to transform the gas into a solid, but they also created
the blue parts aren't parallel, because there's a subject in the second part but not in the first. and you are not, not, NOT allowed to ignore "they" in the second part.
and because "scientists" comes before "not only", you must ignore it.