Sigmoid valves
[医] 半月瓣
🧩 词语组成解析
a. S字形的, 乙状结肠的, C字形的\\nn. 乙状结肠
n. 阀门；真空管；瓣膜（valve的复数）
🗣️ 情景例句
You don't know up from down.
你黑白不分。
Misfortune is a good teacher.
不幸是良师。
Excuse me! Are you from the USA?
对不起，你是美国人吗？