I am not Japanese, so I will assume that you have authority on this, solomonko, but I feel it is a little misleading to say directly, "Ri is a Japanese sound," because, while り is commonly transcribed as "Ri," it does not always sound the same to me as an "r-sound" followed by an "ee" sound when I hear Japanese people pronounce this syllable.solomonko wrote:...
Also, I am ashamed to be told that Ri is Japanese sound, I am not supposed to make such a mistake, because I'm a Japanese!
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In particular, the sound, to me, sounds to start with something between an English r-sound and l-sound, and can at times even have a sound similar to the letter d in English.
Probably in most cases, り sounds to start with a sound closest to the letter R in English, but it certainly does not seem to be definitely the case, in my opinion.