Sentence Correction

Friends,
I attended first 200 question from OG. My overall hit rate is ~60%. I have summarized my performance:

Easy questions - 47 correct out of 61 qns.
Medium questions -50 correct out of 93 qns.
Hard questions-21 correct out of 46 qns.

Before I started practising OG, I read Manhattan Sentence correction, Spidey's notes and some basic grammar rules from "The good grammar book" by Michael Swan & Wren-Martin's grammar book ( Read both the books 4 months back). I did not do any other preparation regarding sentence correction.

I dont know how to evaluate my performance. Your suggestions, please.

Next obvious move is take OG-11 & start with diagnostic test.

About the statistics you presented you classified the SC questions into hard/medium /easy categories.
But to check what are your weak areas I'd categorise them into type of SC faced.
Check the OG-11 where each SC question is categorised into type of problem (eg. subject verb agreement etc)

Thanks aim-wsc. As you said I am categorzing the areas in OG where I am weak. Would like to read some review in Kaplan, take a bit pause before proceeding with OG11. Thanks for moving my other post to the appropriate section...