perfectboy, 3q 4 ur advice! When I work on CR next time, I will keep it in mind. I guess the reason why I got those questions wrong is that I interpret the sentence in a wrong way different from the author's true meaning. Not sure, may be....we will see. BTW, I have the same question as jiejie does.
wangy190, you should go around here more often in the forum, and read through those NN's plans, lessons, and advices. Then you may find tons of materials you might wish to study, however, that is impossible to go over them all! Don't be overwhelmed by them, sort out materials that best suit you regarding the time, your level, and your energy. You could get almost everything you need here. After you know what you want, you will be able to find those you need.