Suppose you do this experiment with a friend ,Get hold of a book with a large page size and with lines that go right across the page,Get your friend to hold the book up and to read it with the top of the book just below his eye level,
this means that you can watch the movement of his eyes as he reads the page. if you do this , you will see that you friend's eyes do not make a contunuous forward sweep. instead they progress by little, "jumps" , moving, the stopping as they progress along the line,there has tobe this starting and stopping movement because the eye can see only when it is moving ,every time the eye pauses it sees a phrase or even a sentence, even jumps to the next part of the line,and so on,
谢谢,初来乍到不足之处还望海涵
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