Ball's valves
[医] 鲍尔氏瓣, 莫尔加尼氏瓣(肛瓣)
🧩 词语组成解析
n. 阀门；真空管；瓣膜（valve的复数）
🗣️ 情景例句
When was it built?
它是什么时候建造的？
Weak men wait for opportunity, but the strong men make it.
若者等待机会，强者创造机会。
No. The next development was to carve the characters on a piece of wood.
是的，不象。下一步的发展是将汉字刻在一片木板上。