cons ::= m n ny ng p py ph t ty th c cy ch k ky kh r rh l ly lh h s sh z zh;
short := 3: "a" | "e" | "i" | 5: "o" | 3: "u" | "ü" | "ö";
long := 3: "ā" | "ē" | "ī" | 5: "ō" | 3: "ū";
vowel := 5: short | long;

puts (4: "" | vowel) rep[2..4, cons vowel];