Hi,

Mixed with an equal part of water, ethylene glycol, a compound commonly used as an automotive antifreeze, is effective at temperatures as low as –30 degrees Fahrenheit.
A. temperatures as low
B. temperatures so low
C. as low temperatures
D. as few
E. as little

The OA is A; I eliminated A becasue I thought temeratures are not parallel to 30 degrees.

I chose C, I can not see any problem in C; is it becasue 'as+adj+n+as' ?

IMO C is incorrect because "temperatures" is not singular. The correct structure is ...as [adj] a temperature as...

do you mean that noun put in between as...as must be singular??

ethylene glycol is effective at temperatures as low as –30 degrees.

I believe that "effective at temperatures" is correct.

"as low as –30 degrees" is also correct.

As we say -
as twice as

Sorry - I don't know any grammar rule here.

Manhattan Staff can explain about any grammar rule that has applied here.

-30 degrees is a temperature, so there is perfect parallelism in A. For this one you really just need to be aware of your idioms so you can see clearly why C and the others are incorrect..

_________________
Tim Sanders
Manhattan GMAT Instructor

1.i am also confused why c is wrong.

2.are we allowed to say:
...is effective at as low as –30 degrees Fahrenheit.

Manhattan staffs, thank you so much.
please clarify me.

the most concrete reason is that "at" is a preposition. prepositions must be followed by nouns; "as low..." is not a noun. (by contrast, note that "temperatures" -- which follows "at" in the correct answer -- is a noun.)



no, for the same reason.

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Being well-dressed gives a feeling of inward tranquillity [that] religion is powerless to bestow.
C.F. Forbes

thanks for ur explanation Ron, however ,i am still not totally understanding the as adj noun as... construction here.
i see another similar question here:
the-environmental-protection-agency-frequently-puts-t2469.html
The Environmental Protection Agency frequently puts mandatory controls on toxic substances that present as little risk as one in a million chances to cause cancer.
(A) as little risk as one in a million chances to cause
(B) as little risk as one chance in a million of causing
(C) as little risk as one chance in a million that it will cause
(D) a risk as little as one chance in a million for causing
(E) a risk as little as one chance in a million for it to cause
in the question cited above , the OA is B.
however there is some contradictions between these two questions.
in ur explanations i quoted,because at is a preposition, there should be a noun following it.
however , in the second question, i think that "present" is a transitive verb and there should be a noun following it immediately as well;but as we see, the answer to the second question is B and the verb present is immediately followed by as.
so what is the difference between them?
please clarify me and thank you so much.

hi,
please don't post questions on the wrong thread. you actually included a link -- you should have posted this question over there, not here.

in general, there are slightly more complex constructions -- such as adj + noun -- that can be used in the same ways as nouns themselves can.
for instance, in is a preposition.
it can be placed right in front of a noun: i am in school.
it can be placed in front of adj + noun:xxxx happens in two sets of circumstances.
in the same way, it can also be placed in front of larger constructions that fulfill the same role as a noun. in this case, "as little x as y" plays the role of a noun.

here's another set of three examples, all of which are correct:
the virus is found in humans.
the virus is found in most humans.
the virus is found in as much as 80% of the human population.

_________________
Being well-dressed gives a feeling of inward tranquillity [that] religion is powerless to bestow.
C.F. Forbes

HI，RON

sorry for bumping this old thread！

since as +adj+noun+as can function in almost the same way as noun

How could C ”as low temperatures as“ be wrong？

Is it because 1. fatally awkward for using two preposition in succession？ 2. the parallelism dictates A？ noun as low as --- noun

am I thinking right？？？

please clarify，thx

The idiomatic expression "as _____ as" needs to include an adjective, not a noun:

As low as
As smart as
As red as

As chair as ???
As rocket ship as ???
As temperature as ???

Notice that (C) uses this third expression "as (low) temperatures as"

Idiomatically wrong.

_________________
Joe Lucero
Manhattan GMAT Instructor

I miss this point.

thx, really appreciate your help

:)

_________________
Tim Sanders
Manhattan GMAT Instructor

sorry for bumping the old thread！

correct sentence in prep( already stated above):The Environmental Protection Agency frequently puts mandatory controls on toxic substances that present as little risk as one chance in a million chances to cause cancer.

so here we also get a “as （little）risk as” here（that construction appears in the correct answer choice）

is this constructure different from the one we have discussed ：“as （low） temperature as”？

or just because the construction ”as （low） temperature as“ is wrong for immediately following the preposition ” at“

more generally, you can't have "as + adj + PLURAL + as...". this construction is only ok if the noun is singular.
e.g.
i have never met as despicable a person as your sister's boyfriend.
or
i have never met a person as despicable as your sister's boyfriend.
both correct

--

i have never met people as despicable as your friends.
--> correct
* BUT *
i have never met as despicable people as your friends.
--> incorrect.

by the way, this is not something i ever learned consciously, but it's something that i can figure out by considering enough examples.
this point is an excellent illustration of why it's important to develop an intuitive feeling for the way the language works. no one is going to learn -- or teach -- all of these things as "rules", but, by observing the language with an eye toward developing your intuition, you'll be able to figure a lot of them out.

_________________
Being well-dressed gives a feeling of inward tranquillity [that] religion is powerless to bestow.
C.F. Forbes