马桶椅的英文：
（从前的一种刑具）cucking stool

stool是什么意思：
n. 凳子；大便，粪便
v. 长新枝；分檗

Between two stools you fall to the ground
脚踏两条船,迟早会落水

a rickety stool, table, bed, etc
快要散架的凳子、 桌子、 床等

The stool may contain blood and mucus.
粪便或会带血及黏液。

The sample contains stool and digested blood.
样本里含有粪便和血液。

Between two stools one falls to the ground
脚踏两头要落空