Howdy! I think I might be able to help a little.
[*]are there any suggestions where i should focus on regarding my verbal preparation?
are there any topics where people can generally easier improve their score with?
Improving your Verbal score is a balance of learning the question types, becoming comfortable with breaking down arguments and identifying assumptions, and increasing your formal, academic grammar knowledge. Aside from working on each of these skills individually, I recommend that you add reading to your study plan. You should set aside and hour or so each day to just reading high quality material. This will expose you to proper grammar and style. You will learn new vocabulary and expose yourself to topics that you may not be familiar with. And you will improve your comprehension.
So choose some high quality sources, like The Economist
, The Wall Street Journal, and The New York Times to read from. Read articles on topics you normally wouldn't. Read actively, which means you are searching for meaning, identifying main ideas, understanding the relationship of paragraphs, and seeking out the author's tone and motivations. Doing this each day will have a beneficial effect across the whole verbal section.
[*]as i am running out of quant questions in OG13, can u recommend any good source? should i use the official quant review for additional practice, or can u recommend buying question packs for gmat prep, or maybe sth else?
With only a short period left before the test, I would recommend going through OG13 again. Focus on improving on questions that you have already seen and use it as a way to refresh skills and concepts that you haven't seen before. Also, for Verbal practice you could always use LSAT reading materials, which tend to be similar to the GMAT.
[*]i noticed that i often have timing problems. are there any good articles or recommendations regarding timing strategies?
Pacing is crucial to your success.
That's great that you want to focus on it. I would recommend setting a timer every time you answer questions from here on out. This will give you good practice. Also taking full practice tests will be another way to practice pacing, so definitely plan for a few more practice tests.
In terms of how to pace, I recommend the following the resources: http://magoosh.com/gmat/2012/pacing-and ... -the-gmat/
[*]what question level am i expected to solve (according to the MGMAT OG archer there is a separation in easy, moderate, hard, devilish for OG13 questions) in average for a low 600's score and what percentage of these questions should i generally solve correctly?
Scoring is hard to predict. It is not just the level of questions you solve that matters. It also matters if you leave questions blank or skip questions. Ultimately it is an extremely complex process that determines your score, and it all depends on the CAT. To score 600 or higher, you will probably need to answer some of the harder and maybe even a devilish question correctly. But again this is a huge simplification of the process that goes into scoring.
I hope you find some of this helpful.
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