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My (Vietnamese) wife is a big fan of Miss Saigon--but is disappointed that the song lyrics do not make any sense. She says that perhaps the last line ("vao nyay moy") is probably "vao ngay moi" (with some accent marks). "Vao ngay moi" translates to "on a new day."
ぼくのベトナム人の妻はミスサイゴンの大ファンなんだけど、その歌詞についてはまるで意味をなさないってがっかりしてるよ。たぶん、最後のヴァオニャイモイはヴァオガイモイ(本当はアクセント記号がいくつかつく)じゃないかって言ってる。ヴァオガイモイは訳すと「新しい日々で」。
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I m Vietnamese, and I have been listening to the new 2014 International Cast in West End, and it sounds like they are saying: chúc vui vẻ (Dju vui vay) (Which means "wishing you happiness") and I couldn t figure out what the second line said, but from above: Vào Ngày Mới (Vao nyay moy) (which means "on to a new day") makes sense.
So In short: Chúc Vui Vẻ Vào Ngày Mới (Wishing you happiness on to a new day)
I have a friend who was actually in Miss Saigon and unfortunately the song is gibberish. The composers basically wrote the lines based on a conversation with a Vietnamese person and wrote the lyrics phonetically. So, perhaps there is a deeper meaning hidden in there somewhere but it's largely BS.