黑板擦

wèi le chè dǐ fáng chén zài hēi bǎn cā de xià duān zhuāng shàng le yī gè kě yí xìng de jiē fěn hé

为了彻底防尘，在黑板擦的下端装上了一个可移性的接粉盒。

In order to prevent the ash completely, the lower end of the eraser for blackboard is provided with a movable ash receiving box.