hello, I didn't want this thread to go to the bottom of the food chain before someone realizes. Since you've already had a grasp on the quantitative part, I figure I'd give some suggestions regarding the verbal section.
I, too, have been struggling with the verbal section. Just like you said, the V score has been pretty unpredictable for me. My suggestion would be to do a practice test, one that you are able to go back to and review your mistake. GMATPrep is a good source, though there's no explanation for questions (a google search might just do the trick). Figure out what your weak points are (you can do this by tallying up how many type of questions you missed for the types of verbal questions -sentence correction, critical reasoning, and reading comp). Once you do this, you have a pretty good grasp as to what you need to work on. Having taken the real GMAT already, I assume that you kind of already know what your weak point is. Almost always, verbal section just requires meticulous practice and reviews. For sentence correction, I recommend you get the Manhattangmat book on sentence correction (it has helped many people here, including myself). For reading comprehension, just got to do practice - and practice - and practice. For critical reasoninig, I personally recommend the PowerScore GMAT Verbal Bible, for which it goes into details of each section of the verbal part, and I found the critical reasoning to be pretty helpful. My score, prior to practice and studying, has been hovering around the 27 to 30-ish for verbal. After some time practicing, I've improved to a solid 40 now. I find myself getting a lot of sentence corrections right and SC used to be my weakest topic. With just 20 days left (probably just 17 days left), I'd recommend just doing as much practice as possible and make sure you review your mistakes...ask yourself, why did you get it wrong?
I wish you the best of luck and I hope you achieve your target score (though 680 is already an awesome score)
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