In my Khmer (Cambodian) class, I learned two new words. One was "Chlong" ឆ្លង which means "to cross" and the other was "tonle" ទន្លេwhich means "river."
Confident of myself, I tried to put them together in a phrase. So I proudly proclaimed to my English students: "I want to chlong tonle (cross the river)." And they all laughed to my astonishment. Little did I know that "chlong tonle" was a Cambodian idiom which means: "to give birth; to deliver a baby." Now I really know why they laughed.
Ahh... as they say: prudence is the hallmark of an accomplished man. I better learn to keep my mouth shut next time (or stick to English).