Highlighting text is often not an effective way to learn. Highlighting (marking, underlining) important words or sentences often doesn't work. This way, you often focus too much on individual facts and miss the bigger picture. Additionally, you can lose the overview. It can work: use highlighting to bring structure to the text. For example, use pink for the concepts of the text and yellow for the details. Also, be critical of how much text you highlight. Read the text through once before you start highlighting. This way, you better understand what is important information and what is not. What works even better is to write down from memory what you remember after some time (and then look up what you don't remember), answer questions about the text, or create a diagram of the learning material. That way, you learn even more actively.
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