The following reasons may have contributed to such confusion:
1.The "old prep" is too old for you.World is changing and the GMAC is changing even faster form the publication of prep to comtemporary.
2.The prep,issues taken from official stimulation tests,is more flexble than OG.You can compare such situation to what happened when we are in school:The real test is always more difficult than the sample question in our textbook,which just tells you the way of thinking.
suggestion:
1.Focus on the way GMAC thinks and take it just as book full of mentioned sample questions that pertain more to thoey than to real Qs.Let's call it a "theory book".
2.Prep,the counterpart of "theory book",put more attaion on real questions you will meet on the test day.Actually,prep is said to be composed of real questions appeard in earlier real tests and can be most representive.
3.I recommend you to finish OG first.When you have fully mastered the basic principal rules,apply them to prep,the real test.Theory serves the practice.
Hope it helps!
-- by 会员 jtrchina (2010/4/25 20:39:20)