Vietnamese → Japanese
Japanese uses 31 sounds. You already own 15 of them from Vietnamese. The other 16 are the work — and 13 of those are the dangerous kind: close enough to something you already say that you will substitute them without hearing yourself do it.
The silent swaps
Your mouth has something close enough to reach for. These survive for years precisely because they sound right to you — the fix is hearing the difference first, not trying harder.
the move: velar → palatal
Japanese: person · written "ひ hi", "ひゃ ひゅ ひょ"
German ich-Laut — h in front of i gets palatal.
Your /x/ is the one in không (no; not; zero).
the move: labiodental → bilabial
Japanese: winter · written "ふ fu"
Blow gently between the lips. Teeth never touch — this is not English f.
Your /f/ is the one in phở (phở (noodle soup)).
the move: longer
Japanese: grandmother · written "ああ ā", "アー"
Length is meaning: おばさん obasan is 'aunt'.
Your /a/ is the one in ba (three; father).
the move: longer
Japanese: grandfather · written "いい ī"
Your /i/ is the one in đi (to go).
the move: longer
Japanese: number · written "うう ū", "ウー"
Your /ɯ/ is the one in thư (letter).
the move: longer
Japanese: teacher · written "えい ei", "ええ ē"
ei is normally said as a long ē, not as two vowels.
Your /e/ is the one in đêm (night).
the move: longer
Japanese: Tokyo · written "おう ō", "おお"
Your /o/ is the one in cô (aunt; Miss; female teacher).
the move: close, but not identical
Japanese: who · written "だ で ど d-"
Your /ɗ/ is the one in đi (to go).
the move: close, but not identical
Japanese: evening · written "ば び ぶ べ ぼ b-"
Your /ɓ/ is the one in ba (three; father).
the move: alveolar → alveolo-palatal
Japanese: sushi · written "し shi", "しゃ しゅ しょ sh-"
Not English 'sh' — tongue flatter and further forward.
Your /s/ is the one in xin (to ask for; please).
the move: voiced
Japanese: rice, meal · written "が ぎ ぐ げ ご g-"
Many Tokyo speakers nasalise it to [ŋ] inside a word.
Your /k/ is the one in cá (fish).
the move: velar → uvular
Japanese: book · written "ん n"
A beat of its own, and it changes colour: [m] before p/b/m, [n] before t/d/n, [ŋ] before k/g, uvular [ɴ] at the end.
Your /ŋ/ is the one in ngon (delicious).
Words you may say identically
Two or more Japanese sounds landing on one sound of yours. Until the ear separates them, the mouth cannot — which is what the ear trainer is for.
Genuinely new
Nothing in Vietnamese sits close to these. They sound foreign in your mouth — which is the good news: you can hear that you are not saying them yet.
cherry blossom
One tap — between an English r, l and d. Never the English r.
Closest thing you own: — but nasal → tap.
time
Closest thing you own: — but nasal → affricate, alveolar → alveolo-palatal.
small
Closest thing you own: — but plosive → affricate, alveolar → alveolo-palatal.
Rhythm and pitch
The layer spelling never records, and the one that makes a correct sentence still sound foreign.
| Vietnamese | Japanese | |
|---|---|---|
| Rhythm | Syllable-timed, one tone per syllable | Mora-timed |
| Stress | No lexical stress. Every syllable carries its own tone and its own full vowel, and none is reduced. What sounds like stress to an English ear is a syllable holding its tone longer or louder for emphasis, and grammatical words (đã, sẽ, được) being said lighter and faster than content words. | No stress in the English sense — syllables are not louder or longer, so a Japanese speaker reading English tends to flatten it, and an English speaker reading Japanese tends to hammer syllables that should be even. |
| Pitch | lexical tone — pitch changes the word | Japanese sits between the tone languages and the stress languages, and gets its own name for it: pitch accent. A word has at most ONE place where the pitch drops, and where that drop falls is part of the word. 箸 hashi (drop after ha) is chopsticks; 橋 hashi (drop after shi) is a bridge; 端 hashi (no drop) is the edge. Unlike Cantonese there is no contour to learn per syllable — only 'where does it fall, if at all'. Tokyo and Osaka disagree about the answer for many words, and both are correct. |
What you have that Japanese doesn't
20 sounds with no job in Japanese. They are not mistakes — but they are where an accent leaks in, because a sound you own is easy to use when a hard one is due.
The honest caveat
This is a prediction from the shape of two sound systems, not a recording of you. It says what your inventory makes likely — it cannot know that your Vietnamese has a regional variety that already owns one of these, or that you learned Japanese from someone whose accent you copied. A teacher listening to you beats it. Use it to know what to listen for.
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