There are certain concepts that don’t translate well over language borders. It is difficult to convey a nuance of something to someone which she is not able to conceptually grasp (be it mentally or linguistically).
There are obvious things like Phonems (everyone loves those 😉 ) …
- “L” vs. “R” in some Asian languages
- “B” vs. “V” in Spanish
- Turkish “ı” and Korean “ㅡ” ([ɯ])
- [x] vs. [ç] in German “ch”
… and less obvious things like … colors. 🙂 The most interesting thing is that almost all languages seem to make a black<->white and a red/yellow<->green/blue distinction. I came across a Wikipedia article talking about distinguishing blue from green in language as not all of them do. Another interesting concept that was described is that in some languages it is also hard to distinguish blue from black. There are studies showing the interdependence of color concepts:
According to Brent Berlin and Paul Kay‘s 1969 study Basic Color Terms: Their Universality and Evolution, distinct terms for brown, purple, pink, orange and grey will not emerge in a language until the language has made a distinction between green and blue. In their account of the development of color terms the first terms to emerge are those for white/black (or light/dark), red and green/yellow.