| 摘要 |
PURPOSE: A tidy blackboard is provided to prevent a user from obtaining chalk powder during writing or deleting characters. CONSTITUTION: A fixed type blackboard receives chalk or chalk powder which are dropped down to the bottom through a basket by bending the bottom of the black board. The bottom of the blackboard is bent. When the chalk powder is dropped down to the bottom, the bottom of the blackboard includes a slope to store chalk powder in a powder case.
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