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Hi,
This question is for experienced GMAT Instructors or anyone with good GMAT score(740+).

My progress in SC so far:
1) Completed all the videos and additional reinforcement questions on gmatprepnow website.
2) Completed the OG15 SC part with around 50-60% accuracy

Still struggling with the concepts and its applications to handle questions. Need to improve.
Please suggest some effective resources to hit the bull's eye. Any suggestions or tips would be much appreciated but please be crisp. I also wanted reviews about Manhattan GMAT Sentence Correction as someone has suggested me this book.