Interesting. I don't know about Thai, but for Mandarin, the issue is similar - g/k, d/t, b/p in English all are (voiced and unaspirated) or (unvoiced and aspira

Interesting. I don't know about Thai, but for Mandarin, the issue is similar - g/k, d/t, b/p in English all are (voiced and unaspirated) or (unvoiced and aspirated), while what's in Pinyin denoted g/k, d/t, b/p is (unvoiced and unaspirated) or (unvoiced and aspirated). In other words, if you put the 4 combinations in a square, in English (and German), 2 are used that are on a diagonal, while in Mandarin, 2 are used that are in the same row (or column, as the case may be). In Hindi apparently are 4 are used. ETA: Wikipedia says this: "Between pairs of stops or affricates having the same place of articulation and manner of articulation, the primary distinction is not voiced vs. voiceless (as in French or Russian), but unaspirated vs. aspirated (as in Scottish Gaelic or Icelandic)." https://en.wikipedia.org/wiki/Standard_Chinese_phonology#Consonants https://en.wikipedia.org/wiki/Standard_Chinese_phonology#Con...