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这种笔,既能当钢笔,又能当铅笔,还能当圆珠笔和毛笔呢。如果你想用其中一种笔,只要你直接按一下
This pen, both as a pen, but also as a pencil, but also when the ball-point pen and brush it. If you want to use one of the pens, just click on it