Ok. I tooked GMATprep 1 last night. After five month not touching GMATprep material, I forgot most of the questions. Therefore, the test will probably reflect better of my ability.
I scored 680 on GMATprep1 with Q51 V30
For the Q section I missed question# 1, 17, 30, 33. (1PS 3DS) I can't believe I missed the first question. That is totally because I didn't pay close attention to the question. It is something square, but I interpreted as something times 2.
For the V section, I missed question# 1, 4, 5, 15, 17, 23, 24, 25, 26, 30, 31, 32, 34, 39, and 41 (6SC, 2CR, 7RC) I know I am weak in RC. There is one passage I totally don't understand what it is saying; therefore, I missed all four questions for that passage. I think so far my CR is strong. Technically I should say I only missed one CR question. The other one because I ran out of time so I guessed an answer without even reading the questions and moved on. What surprises me is SC. In knewton CAT, I usually one miss about 1 or 2 SC questions. Now, I can tell how easy knewton CAT's SC questions are.
For the rest of the days left until my exam, I am going to focus more on SC. As for RC, it purely depends on my luck now. If I don't get some RC passages that I totally cannot understand, then I will be fine.