I , a nonnative english speaker, wanted to obtain GMAT score above 650, verbal-32 and quant-48. At my first attempt, i appeared for MGMAT-1 one year ago and got 600, verbal-31 and quant-45. But the nightmare was that in 2011 january i finally got 500, verbal-16 and quant-45 on the real exam. However, after one and half year within which i completed my MBA(Marketing) and joined in a Bank as professional. During my job performance, i thought to do more than my present, so i decided to appear for the GMAT exam again and left the job forever since three months only for reading gmat. This time i sited for the same MGMAT test 1- and got 690, verbal-34 and quant-50. so i feel better in relation to my past experience. I dare to be confident to get for the 2nd attempt at least 650 on real exam. But the nightmare was come again. I got 530,v-18 and q-46, AWA-5.5, IR-5 on sunday last(5/8/12). My quant part was completed 15 minutes earlier, causing 23 minutes break. after this break my mental ability seemed to fresh and energetic. i picked each verbal choice reading well, but at the end the worst result appeared on the screen. I know rules for approaching from mgmat forum and all 9 books of mgmat, but i can not apply to the real exam. What is fault with me here ? I got 650 and 690 in new gp 1 and 2. I used OG -12,13, Gp question solution from mgmat forum.

Present GMAT:
IR is much more easier than that of gp
quant over flooded by modulus, inequality, and geometric progression.
verbal: i could not keep that in my mind to present, in cr- assumption, weaken, and evaluate. in rc- about genetic classification based on cultural traits, employees downsizing is a mistake of organizational managers. - in sc i did not form any rules.

why can't i apply my learning in gmat ?
what are the lackings in my learning?
how should i study again for this?
what i need to have for GMAC's verbal style or pattern?
Can't it be at all possible to overcome my 16-18 boundary forever?

PLZ help !