Sentence Correction OR
Process of Elimination: The GameHere's the thing about Sentence Correction - you don't care what makes an answer right, you care what makes an answer
wrong. Therefore, it is a game of memorization.
I am convinced that most people can be taught about Subject-Verb agreement, Modifiers, and Parallelism. Based on my personal experience, knowing the basic rules of these three topics will allow you to answer 100% of 500-600 level questions, 50% of 600-700 level questions, and maybe 10-20% of 800 level questions. The rest of the time, you will need to memorize and be able to recall specific idiomatic rules to narrow down answer choices. When you are confronted with a SC problem, your main task is to identify as many errors as possible in the answer choices. Splits are nice if they happen, but sometimes you just don't have that luxury.
EXAMPLE -
Proponents of artificial intelligence say they will be able to make computers that can understand English and other human languages, recognize objects, and reason
as an expert does-computers that will be used to diagnose equipment breakdowns, deciding whether to authorize a loan, or other purposes such as these.
A) as an expert does - computers that will be used to diagnose equipment breakdowns, deciding whether to authorize a loan, or other purposes such as these
B) as an expert does, which may be used for purposes such as diagnosing equipment breakdowns or deciding whether to authorize a loan
C) like an expert - computers that will be used for such purposes as diagnosing equipment breakdowns or deciding whether to authorize a loan
D) like an expert, the use of which would be for purposes like the diagnosis of equipment breakdowns or the decision whether or not a loan should be authorized
E) like an expert, to be used to diagnose equipment breakdowns, deciding whether to authorize a loan or not, or the like
STUDENT888 APPROACH
My first screen is parallelism. I do NOT go looking for the right answer, I go looking for wrong answers. Two jump out at me.
A) as an expert does - computers that will be used to
diagnose equipment breakdowns,
deciding whether to authorize a loan, or other purposes such as
theseNOT PARALLEL - Incorrect. Also "these" cannot be used as a stand-alone pronoun.
E) like an expert, to be used to
diagnose equipment breakdowns,
deciding whether to authorize a loan or not, or the like
NOT PARALLEL - Incorrect.
Okay, I eliminated two wrong answers. Here is where knowing the rules comes into play.
B) as an expert does,
which may be used for purposes such as diagnosing equipment breakdowns or deciding whether to authorize a loan
"Which" can only modify the noun immediately preceding it. Therefore, this answer is incorrect, as the modifier in this sentence is about the computers, not the expert.
That leaves us with two answer choices.
C) like an expert - computers that will be used for such purposes as diagnosing equipment breakdowns or deciding whether to authorize a loan
D) like an expert, the use of which would be for purposes
like the diagnosis of equipment breakdowns or the decision whether or not a loan should be authorized
Whenever a sentence is changed, I always check to make sure it retains the original meaning. "Like an expert" is okay because "like" is used here as a comparison. However, the second "like" in answer choice D is being used to introduce an example. "Like" can never be used to introduce an example, therefore D is incorrect.
The correct answer is
C.
Really, beyond a basic level, it will come down to how many of the rules you can remember. I think Sentence Correction is the area that has the biggest tendency to fluctuate because your performance depends in large part on whether the SC problems you encounter on test day contain the errors you have memorized.
Here are a couple off the top of my head -
"This, These" - cannot be stand-alone pronouns
"Whether" is better than "If" for two options
"Like" cannot be used to introduce examples
"Many, More, Fewer" for countable objects
Units of measurement are not countable objects ("less than 20 dollars" NOT "fewer than 20 dollars").
Use "THAT" for essential modifiers (no comma); use "WHICH" for non-essential modifiers (comma)
Modifiers must be parallel to the subject ("Unlike the Brontes and Brownings, the adulation..." is incorrect because "adulation" is not an author)
"To a height of" is NOT the same as "As high as"
"Both-And"
"Either-Or, Neither-Nor"
Only "AND" can create a collective noun (Beth AND Sue ARE tall; Beth as well as Sue IS tall)
The phrase "having for" is almost always wrong
The phrase "to have the ability to/for" is almost always wrong
And so on ad infinitum.
I've gotten questions asking me about how to get better at SC. My only advice is to understand that SC problems are entirely Process of Elimination - ALWAYS look for errors, NOT correct answers. In my opinion, if you've already gotten the basics down, then there is literally nothing more you can do except memorize the rules of GMAT grammar (Manhattan SC is a great source) and get lucky.