For all thes areas, go through all questions you have done so far and see if there s a trend I questions that you get wrong. If you identify such a trend then work to address that weakness.
For RC, please read the passage and each answer option CAREFULLY. Remember, EACH WORD HAS SIGNIFICANCE. I just cannot stress this enough. Numerous times, I used to get a question wrong just because I failed to read all words in the options carefully. It might also be useful if you use a strategy of elimination. Study each option and try to find some fault in it that renders it incorrect. Just use these strategies and practice. They worked for me big time.
For the remaining areas, I would suggest brushing up your basics. Knowing the fundamentals inside out is a must. Once that is done, just practice non stop. Try to find the shortest possible solution, that is the one which takes least time for the questions that you can do easily. That way you will have more time left over for tougher questions. Also try to minimise careless errors. All this can only be done via practice and mock tests.
Let me know if you need any help from my side.
Cheers
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