Sentence Correction

Hi,

I have been getting a score of 19 in verbal. I have 27 days in hand. What should be done in the time period to improve my verbal score. Further i have practiced the og rc's in feb will doing them again be waste of time.
My verbal accuracy is as follows
sc easy medium 76% hard 48%
rc 48 percent hard rc's cant do end up guessing
cr 70 percent

Kindly guide how to improve.