Of all the three questions types on the GMAT Verbal section — Sentence Correction, Critical Reasoning and Reading Comprehension — SC is the question type that most people preparing for the GMAT tend to take a liking towards (it goes without saying that RC is the most hated). This fancy towards SC often leads to aspirants really digging deep into Grammar. So much so that they start spouting Grammar jargon!

But there is more to GMAT Sentence Correction than the rules — a process or approach that will ensure that you do not become/remain a Grammar expert but become a GMAT SC expert.

So here is the list of Dos and Donts that will help you increase you speed and maximise your accuracy on GMAT Sentence Correction. I have classified them into four categories: Error Identification, Error Resolution, Option Elimination & Increasing Speed

ERROR IDENTIFICATION

1. Do not try to fix the sentence, look out for differences between answer options

This is the rightly the first rule. The moment you spot an error on a sentence, do not correct it and look for that version in the options. For example, on questions that test parallel structure, the verb can be expressed in two forms. There is always more than one way to correct a sentence so do not do it yourself.

Also, more importantly, GMAT test-setters are known to fix the most obvious error and deliberately introduce an error in another part of the sentence. So, always compare between options, especially the entire length of the option and not just part of the option. This post explains this best The Other Error

 So as a rule the differences between answer options should be the best clue as to where the error lies.

2. Look out for Subject & Pronoun errors

The biggest skill to possess while solving  GMAT SC questions is the ability to spot discrepancies in Subject & Pronoun usage. So whenever two options differ in their usage of singular/plural verb to go with subject or with respect to pronoun usage, it should immediately register, everything else follows from there. In case you missed the post on, you can read it here Identifying the subject

3. Always lookout for the 3/2 Split

At the least about 7-10 questions out of the 15-16 Sentence Correction questions on the GMAT Verbal section will have the 3/2. It is the fastest way to spot errors and eliminate more than one option at a time. It has been discussed in detail here and here.

ERROR RESOLUTION

4. Resolve the Main, Big-Ticket Errors first

When comparing two options test-takers sometimes tend to unnecessarily get caught up in trying to resolve minor differences. For example, took into account only or only took into account. The same two options might have a main, big-ticket difference that you need resolve first like the usage of its and their.

If the 3/2 split shows up a pattern at both the left-side and the right-side, first resolve the side  that you can link to a rule. For example between an is/are split on one side and a spilt that you cannot link to a rule, say stationary crests and troughs vs crests and troughs that are stationary. resolve the is/are issue first.

As a process proceed from resolving major errors to resolving minor errors. A post about what minor errors can be found here — The Minor Error

5. Do not get stuck with particular phrases move on to other parts, there are more errors than you think there are

One reason why test-takers lose speed and accuracy is that they get stuck to one part of two options. They keep repeating the variations in the two options with respect to that part of the sentence over and over again hoping that their ear will lead them to the right answer. In reality reading over and over again only makes both options seem right.

Whenever you find yourself unable to resolve which option to choose with respect to a particular part of a sentence, move on to other parts of a sentence; all options have more than one error. The test is designed to be completed on time provided you are doing the right things.

OPTION ELIMINATION

6. Lookout for Passive Voice to eliminate options

The ability to spot passive voice immediately is a huge advantage since it helps you eliminate an option at a top-level without having to split hairs or evaluate finer points with other options.

Passive voice is not preferred on the GMAT, except on very rare questions where all options are in passive voice.

7. Do not eliminate options because they are unfamiliar; unfamiliar need not mean incorrect

The reflex reaction of most test-takers to an unfamiliar usage or phrase is to label incorrect/awkward/wordy,. Once they do this sort of a labelling they do not even evaluate that option properly (is the main error sorted) before eliminating it as a contender.

Our ears are not tuned to Grammar but to Familiarity but remember unfamiliar need not mean incorrect — a concept that has been discussed during this course of this post — Idiomatic Usage

INCREASING SPEED

8. Ignore non-underlined parts that have ‘which’ followed by information within commas

Whenever information is presented in the non-underlined part using a comma followed by a which, ignore that part. It is deliberately inserted to increase the spatial gap between two parts so that test-takers do not spot the error. For example the subject is singular but the part with the which has a plural term followed by the verb in plural, leading to test-takers missing the disagreement between the subject and the verb. This has been discussed in this post —Which Vs That

9. Read long sentences with Xs and Ys

One of the ways of crashing your solving time on GMAT SC is to read medium-long sentences in terms of X and Y. This has two benefits:

• it helps you listen only to the structure of the sentence
• helps you navigate faster through options by not having to read the entire sentence

You can learn how to do this by going through the answer explanations of SC questions in the OG. Since repeating unnecessary information with every answer option was a burden, the makers of the OG decided to use Xs and Ys in the answer explanations. This is a very important skill to develop since it can really help you sort out SC questions in under a minute.

10. Remember, the sentence may be right as it is!

I spend quite some time with GMAT aspirants during the period they take their mocks. After every mock students usually get their laptops along for a one-on-one session with me to assess and identify a plan of action to improve their score by the next test.

One of things that has consistently come up during these sessions is that on SC, whenever the sentence is right as it is, test-takers have got the question wrong.

Since it is called Sentence Correction, a high percentage of test-takers assume that there is something wrong with the sentence  as it is! Even if they are unable to pin-point any error on first reading they compare the sentence with the rest of options and are pre-disposed to choosing an option apart from the first one.

As with with CR and RC, so with SC option (A) can be correct. So do not waste valuable time trying to forcibly attribute errors. You will have at least 1 or 2 questions out of the 15 Sentence Correction questions where the sentence is correct as it is!