Here is some advice you can follow to improve your verbal and quant skills. I’ll start with verbal.
For example, let’s say you are reviewing Critical Reasoning. Be sure that you practice a large number of Critical Reasoning questions: Strengthen and Weaken the Argument, Resolve the Paradox, find the conclusion, must be true, etc. When you are working on learning to answer questions of a particular type, start off taking your time, and then seek to speed up as you get more comfortable answering questions of that type. As you go through the questions, do a thorough analysis of each question that you don't get correct. If you missed a weaken question, ask yourself why. Did you make a careless mistake? Did you not recognize what the question was asking? Did you skip over a key detail in an answer choice? Getting GMAT verbal questions right is a matter of what you know, what you see, and what you do. So, any time that you don't get one right, you can seek to identify what, if anything, you would have needed to know in order to get the right answer, what you had to see that you didn't see, and what you could have done differently to arrive at the correct answer. Follow this process for all verbal topics. I understand that you are looking to improve Critical Reasoning in particular, but to get to a 730, you will want to improve in all aspects of GMAT verbal.
When practicing Reading Comprehension, you need to develop a reading strategy that is both efficient and thorough. Reading too fast and not understanding what you have read are equally as harmful as reading too slow and using up too much time. When attacking Reading Comprehension passages, you must have one clear goal in mind: to understand the context of what you are reading. However, you must do so efficiently, so you need to avoid getting bogged down in the details of each paragraph and instead focus on understanding the main point of each paragraph. That being said, do not fall into the trap of thinking that you can just read the intro and the conclusion and thereby comprehend the main idea of a paragraph. As you read a paragraph, consider how the context of the paragraph relates to previous paragraphs, so you can continue developing your overall understanding of the passage. Furthermore, as you practice Reading Comprehension, focus on the exact types of Reading Comprehension questions with which you struggle: Find the Main Idea, Inference, Author’s Tone, etc. As with Critical Reasoning, analyze your incorrect Reading Comprehension answers to better determine why you tend to get a particular question type wrong, and then improve upon your weaknesses.
The process above can be perfected with a lot of practice. However, keep in mind that GMAT Reading Comprehension passages are not meant to be easy to read. So, to better prepare yourself to read such passages, begin reading magazines with similar content and style, such as the Economist, Scientific American, and Smithsonian.
Sentence Correction, on the other hand, is a bit of a different animal compared to Reading Comprehension and Critical Reasoning. There are three aspects to getting correct answers to GMAT Sentence Correction questions: what you know, such as grammar rules, what you see, such as violations of grammar rules and the logic of sentence structure, and what you do, such as carefully considering each answer choice in the context of the non-underlined portion of the sentence. To drive up your Sentence Correction score, you likely will have to work on all three of those aspects. Furthermore, the reason that your Sentence Correction performance has not improved is likely that you have not been working on all three of those aspects.
Regarding what you know, to be successful in Sentence Correction, first and foremost, you MUST know your grammar rules. Let's be clear, though: GMAT Sentence Correction is not just a test of knowledge of grammar rules. The reason for learning grammar rules is so that you can determine what sentences convey and whether sentences are well-constructed. In fact, in many cases, incorrect answers to Sentence Correction questions are grammatically flawless. Thus, often your task is to use your knowledge of grammar rules to determine which answer choice creates the most logical sentence meaning and structure. This determination of whether sentences are well-constructed and logical is the second aspect of finding correct answers to Sentence Correction questions, what you see. To develop this skill, you probably have to slow way down. You won't develop this skill by spending under two minutes per question. For a while, anyway, you have to spend time with each question, maybe even ten or fifteen minutes on one question sometimes, analyzing every answer choice until you see the details that you have to see in order to choose the correct answer.
As you go through the answer choices, consider the meaning conveyed by each version of the sentence. Does the meaning make sense? Even if you can tell what the version is SUPPOSED to convey, does the version really convey that meaning? Is there a verb to go with the subject? Do all pronouns in the sentence clearly refer to nouns in the sentence? By slowing way down and looking for these
details, you learn to see what you have to see in order to clearly understand which answer to a Sentence Correction question is correct.
There is only one correct answer to any Sentence Correction question, there are clear reasons why that choice is correct and the others are not, and those reasons are not that the correct version simply "sounds right." In fact, the correct version often sounds a little off at first. That correct answers may sound a little off is not surprising. If the correct answers were always the ones that sounded right, then most people most of the time would get Sentence Correction questions correct, without really knowing why the wrong answers were wrong and the correct answers were correct. So, you have to go beyond choosing what "sounds right" and learn to clearly see the logical reasons why one choice is better than all of the others.
As for the third aspect of getting Sentence Correction questions correct, what you do, the main thing that you have to do is be very careful.You have to make sure that you are truly considering the structures of sentences and the meanings conveyed rather than allowing yourself to be tricked into choosing trap answers that sound right but don't convey meanings that make sense. You also have to make sure that you put some real energy into finding the correct answers. Finding the correct answer to a Sentence Correction question may take bouncing from choice to choice repeatedly until you start to see the differences between the choices that make all choices wrong except for one. Often, when you first look at the choices in a Sentence Correction question, only one or two seem obviously incorrect. It may take time for you to see what you have to see. Getting the right answers takes a certain work ethic. You have to be determined to see the differences and to figure out the precise reasons that one choice is correct.
To improve what you do when you answer Sentence Correction questions, seek to become aware of how you are going about answering them. For instance, are you being careful and looking for logic and details, or are you quickly eliminating choices that sound a little off and then choosing the best of the rest? If you choose an incorrect answer, consider what you did that resulted in your arriving at that answer and what you could do differently in order to arrive at correct answers more consistently. Furthermore, see how many questions you can get correct in a row as you practice. If you break your streak by missing one, consider what you could have done differently that would have resulted in your extending your streak.
As with your Critical Reasoning and Reading Comprehension regimens, after learning a
particular Sentence Correction topic,engage in focused practice with 30 questions or more that involve that topic. As your Sentence Correction skills improve, you’ll then want to practice with SC questions that test you on skills from multiple Sentence Correction topics.
Although your quant is stronger, you can follow a similar process for that section. For example, if you are reviewing Number Properties, be sure that you practice 50 or more questions just from Number Properties: LCM, GCF, units digit patterns, divisibility, remainders, etc. When you are working on learning to answer questions of a particular type, start off taking your time, and then seek to speed up as you get more comfortable answering questions of that type.
As you do such practice, do a thorough analysis of each question that you don't get right. If you got a remainder question wrong, ask yourself why. Did you make a careless mistake? Did you not properly apply the remainder formula? Was there a concept you did not understand in the question? By carefully analyzing your mistakes, you will be able to efficiently fix your weaknesses and in turn improve your GMAT quant skills. Number Properties is just one example; follow this process for all quant topics.
Each time you strengthen your understanding of a topic and your skill in answering questions of a particular type, you increase your odds of hitting your score goal. You know that there are types of questions that you are happy to see and types that you would rather not see, and types of questions that you take a long time to answer correctly. Learn to more effectively answer the types of questions that you would rather not see, and make them into your favorite types. Learn to correctly answer in two minutes or less questions that you currently take five minutes to answer. By finding, say, a dozen weaker quant areas and turning them into strong areas, you will make great progress toward hitting your quant score goal. If a dozen areas turn out not to be enough, strengthen some more areas.
So, work on accuracy and generally finding correct answers, work on specific weaker areas one by one to make them strong areas, and when you take a practice GMAT or the real thing, take all the time per question available to do your absolute best to get right answers consistently. The GMAT is essentially a game of seeing how many right answers you can get in the time allotted. Approach the test with that conception in mind, and focus intently on the question in front of you with one goal in mind: getting a CORRECT answer.
You also may find my article with more information regarding
how to score a 700+ on the GMAT helpful.
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