@Changsoyeon,
Please don't misunderstand. I'm still not where I need to be on RC, but I've improved about 3-4 more correct from where I was before. I'm trying to get to -4 or -3 in the next 2 weeks, but I'm not there yet. Funny enough, I had to return to RC after making some gains in LR but regressing in RC.
My biggest issue in general is timing. Most times, if I review RC and LR passages untimed, I can usually dissect it. But I tend to make silly mistakes under time pressure.
Anyways, I can only give you specific advice on reading to answer "main idea", "purpose" questions -- still struggling with detail Q's.
Reading for Structure:1. I start reading the first paragraph slowly. If I don't understand a sentence, I re-read it. I start picking up the pace if it makes sense.
> I actually noticed something today -- when I lean forward, my pacing slows down and I zoom in. On the other hand, when I sit up straighter I tend to focus more on the "big picture". Ha! 2. After reading the first paragraph (and this is a must for me), I write out
in a few words what I think the main idea of the paragraph is. I keep this in mind and think about how it relates to the 2nd paragraph "Okay, P2 is expanding on P1", "Oops, P2 is narrowing the scope", "P2 intros new idea... okay". Same for P3, P4 etc.
3. As I read through all paragraphs (especially P2 and on) I underline things I think are important, circle terms/positions -- especially those odd-sounding words like "tetra-oxo-bi-carbo-!!"
> Underlining is a work in progress. Some stuff I underline don't even come up in Q's, but I've started underlining less -- I suppose that's progress.4. I always slow down on the last paragraph until I can figure out if something new is in there -- maybe the conclusion! (I've been burned several times)
Not sure how you've been practicing, but I've been doing a lot of individual RC passages. E.g., I'll do Passage 2 timed, review untimed and then check answers; then I'll repeat the process for Passage 3 or 4 of the same RC. etc. Hopefully, this will help me improve my individual timing on each passage which should improve my overall RC timing.
Note: My annotating process is not perfect -- still a work in progress -- but it really helps me understand the structure of most passages. The act of actually writing something down helps me understand better. Now, if I can only get better at detail->Inference questions...
Hope I answered most of your questions