well, for SC correction , htere is no secret! The bes books are :
- MGMAT SC
guide (very good book)
- SC grail aristotle: not bad, I am using it right now, and it is pretty good
You can also have a look at GMAT Club Grammar book
, which is good to remember the fundamentals.
As far as practice is concerned, 1000 SC questions: there is no better way to dip your toes in it.
Don't forget to use an error log
for you to learn from every mistake you do: I think it is better to do 100 SC question and understand them, than 1000 and not havong a clue why you made a mistake.
I hope this help
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