Indeed that is good advice.
Ye,s it is not easy at first but you need to pretend (in a way) that someone has asked you what the main idea of the sentence is in a handful of words. AND you need to remind yourself that this is for mapping purposes and for General Idea and other such questions that can be answered via what we call Initial Reading. You do not need to write down and 'black out' necessarily. The point is valid though- We want general information not specific info as this will not help us.
For example, If the first two sentences state: The Baby Boomer era was characterized by the tension between an attempt to maintain a new moral anti consumerist and rights-based belief system, and a desire to accumulate wealth. The 1990s are replete with examples of purportedly non consumerist philosophies that were turned on their heads such as X, Y, and Z etc etc
Well what is the main idea? What should we take notes on? Ask yourself first: What is the sentence about? Then ask yourself: What else do I know about this...?
S1 (sentence 1): Baby boomer era-main character. tension between new morality and wealth
S2 1990s- ex.s of anti consumerism phil. abandoned
Do we need to know what the specific examples are? no.
As you get better at notetaking you will also get better at filtering out unimportant info. Always remember we want JUST the main idea. Pretend you are the teacher and a student asked you what the main idea of the sentence is (or paragraph or text).
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