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As a student, we see chalks(粉笔)very easily. Most of the chalks are white. Some are coloured. They are about 8 centimeters long. They are used by our teachers. They are pens for our teachers. They use the "pens" to teach us, from "a, o, e" to "A, B, C". We see they become smaller and smaller, while we grow taller and taller. We never think they are important (重要的). Sometimes we use chalks to play with or to throw at one another, until one day when I saw the teachers' hands. They were all white after class. From that moment on, I have a different feeling to chalks.