scratch board的用法和樣例：
例句
- To adjust the height of flashboard to control the liquid level and make the useful froth scraped by loam board.
調節閘板高度，控制液面，使有用泡沫被刮板刮出。 - This paper introduces the fault treatment and improving situation of scraping transporter with round-link chain and glass-ceramic sheathing board in coal washing plant.
介紹了圓環鏈鑄石襯板刮板運輸機的故障處理及改進情況。
