Undefinition
[計] 未定義, 未定界
??? 情景例句
Sure.
不用謝。
We kept on discussing the problem for four hours.
我們持續討論那個問題達四小時。
Goats are also kept. Apart from their milk, the wool from their coats is used in expensive clothing.
除了獲取羊奶之外，從羊皮上剪下的羊毛還用來制作昂貴的服裝。