Yabla video uses of

zài
过去 guòqu
宫廷 gōngtíng
jiàng
yòng
一种 yīzhǒng
jiào
cuò
cǎo
de
植物 zhíwù
进行 jìnxíng
打磨 dǎmó
In the past, the royal palace used a type of plant called horsetail grass for sanding.