Devoiced Vowels - 母音の無声化

This is a trend that occurs when a mora's vowel does not get pronounced fully. That mora is called a vowel-devoiced mora (無声化拍).

Step 1 - Which Vowels?

These sounds have the possibility to become the vowel-devoiced mora in regular speaking speed:

き、く
し、しゅ、す
ち、つ
ひ、ふ、ふぃ、ぴ、ぷ

Step 2 - When?

The above sounds have the possibility to become vowel-devoiced mora when the sound that comes after is a part of:

The 促音(っ) may come before. Also rows of ゃ、ゅ、ょ are included.

Step 3 - More Rules

If the following sound is of か行・た行・ぱ行

Then as principle, that mora will certainly be vowel-devoiced.

If the following sound is of さ行

Then except for when the mora is し、しゅ、す the chances of a devoiced vowel are extremely high. し、しゅ、す will rarely be silenced if the following sound is さ行.

If the following sound is of は行

Then except for when the mora is し、しゅ、す、ひ、ふ the chances of a devoiced vowel are high. ひ、ふ will rarely be silenced if the following sound is は行.

If the following sound is of (っ) + ○

A possibility of a vowel-devoiced mora is existent.