But, you may ask, why is writing necessary? Well, the physical act of writing, with your own hand, brings words and sentences more sharply before your mind and preserves them better in your memory. To set down your reaction to important words and sentences you have read, and the questions they have raised in your mind, is to preserve those reactions and sharpen those questions. You can pick up the book the following week or year, and there are all your points of agreement, disagreement, doubt and inquiry. It's like resuming an interrupted conversation with the advantage of being able to pick up where you left off.
n. 优势,有利条件
vt. 有利于