OFFICIAL EXPLANATIONProject SC Butler: Sentence Correction (SC1)
Quote:
Advanced market research for the MegaTek Corporation predicts that launching a MegaTek Superstore in a given city would only succeed should the density of repeat customers have been greater than 200 per square mile.
• Issues
→ Verb tense
Because the underlined portion is what the MegaTek Corporation
predicts, and because this sentence is best written as a Type 1 conditional, the underlined portion should take the future tense
will rather than
would or
should.
The word "only" tells us that we are or should be dealing with a conditional, in which the IF/THEN clauses are reversed:
Y only if XX, IF clause = the density of repeat customers IS greater than 200 per square mile
Y, then/result clause = launching a MegaTek will succeed
A Type 1 conditional is a statement about a possible real-world condition (repeat customers) and its probable result (success of launch).
A Type 1 conditional is often a prediction or a warning.
-- If THIS thing happens, then THAT thing will happen.
-- Or, THAT thing will happen (main/then clause) only if THIS thing happens (IF clause)
-- In Type 1 conditionals, the verb tenses are
IF simple present, THEN simple future
(In this sentence, we switch the order of the IF and THEN clauses, a switch that is common.)
→ countable/uncountable nouns
The noun at issue is
density, not
repeat customers.
Density anchors the noun phrase
density of repeat customers.Density is the main or head noun in that noun phrase.
Of repeat customers is an adjective phrase that describes density.
Density, like capacity, cannot be counted.
We can use
greater as a modifier but not
numerous.
• British English
Speakers of British English, just be aware that in British English, many constructions that involve
would or
should are allowed in B.E..
Those two words might sound normal to you, but on the GMAT, British conventions are occasionally incorrect.
(In command subjunctive, for example, in B.E. it is common and acceptable to use "should." Not so in U.S. English or on the GMAT.)
THE OPTIONSQuote:
A) would only succeed should the density of repeat customers have been greater than
• verb tenses make the sentence nonsensical: one part takes place in the future and the other, in the past
→
Would refers to the future whereas
should have been refers to the past.
→
Similar error: He would win the tennis tournament only should the top player have been injured.
• we need the verb
will, not would (or should)
→ by definition, someone who predicts, simple present, is predicting something about the future, in which case the simple future tense is needed
• placement of
only is questionable
→
only is often placed after an auxiliary and before a main verb, but in this case,
only is modifying an entire phrase, namely,
if the density of repeat customers is greater than 200 per square mile.→ only should be placed right before that phrase rather than modifying "will succeed."
Right now,
only is placed to suggest that the launch will do nothing other than succeed (the launch could be delayed, for example).
More importantly, in inverted conditionals, we want Y only if X.
• diction: the choice and placement of words is stilted and clumsy—in a word, "awkward."
Do not eliminate an option on the first place on the basis of "awkwardness" or any style issue.
The verb problems in this option make it easy to eliminate.
Eliminate A
Quote:
B) will succeed only should the density of repeat customers be more numerous than
• incorrect modifier: numerous is for countable nouns. We cannot count "density."
• verb tense error
→ we need simple present (only IF the density
IS), not
should• diction error
→ in a Type 1 conditional, in U.S. English and on the GMAT, we do not substitute
should for
ifEliminate B
Quote:
C) will succeed only if the density of repeat customers is greater than
• I do not see any errors
• Correct verbs are used for the main and if clauses
→ recall that we have an inverted structure in which the main/then clause comes before the if clause:
Y will happen only if X happens
(You can flip the sentence around, but it starts to sound stiff: Only if X happens will Y happen.)
In this inverted structure, we need Y = simple future, X = simple present
We have what we need
Y = [launch] will succeed (simple future)
only if X = density IS greater than (simple present)
• uncountable
density is correctly modified by
greater• this option does not contain any errant
should or
wouldKEEP
Quote:
D) should only succeed with a repeat customer density of greater than
• verb tense error
→
should succeed is incorrect.
Will succeed is correct.
• placement of "only" is similar to the problematic placement in option A
•
with is not a strong substitute for IF
→ compare options C and D. Option C is clearer and, I think, more accessible.
"Predict" is a very typical Type 1 conditional statement; the IF/THEN construction suits.
→
with might be okay if option C weren't here.
I don't have to think about this possibility, though, because option C is here.
Option C is far better than this option (and the others).
Eliminate D
Quote:
E) will succeed only with repeat customer density being greater than
•
with is not a strong substitute for
if, especially when coupled with
being• diction/verb tense error
We really do need the Type 1 conditional sentence setup, but in this sentence we do not have an IF clause at all, let alone one in simple present tense
•
with connotes
alongside or
in addition to, neither of which makes a lot of sense and neither of which follows the Type 1 conditional construction
• strange wording
This one I cannot teach in any specific way because usage is idiomatic and gleaned from lots of reading, but a native or nearly fluent speaker would never use these words in this way to express the thought the sentence is trying to state.
Eliminate E
The correct answer is C.NOTESI purposely avoided most discussion of "only" because modals (would, should) and auxiliaries (will) complicate matters, and because I think there are easier ways to eliminate answers.
That said, if you considered (or posted about) only, good for you!
If you did not catch the "only" errors, do not worry.
I am glad to see that different people come at these questions in different ways.
COMMENTSVatsal7794 and
Kirala241 , welcome to SC Butler.
Although this question is fairly easy (I'm looking at the numbers), there is plenty to glean from it.
In addition, people often forget to review or to build and review the foundations.
These answers range from very good to excellent.
Nice work!
03 Dec 2021, 01:00
93%
(01:00)
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