濁点
Dakuten
Voiced sounds marked with two dots (゛)
+12
18 sounds
半濁点
Handakuten
Semi-voiced sounds marked with a circle (゜)
5 sounds
拗音
Yōon
Combined sounds using small や, ゆ, よ
+15
21 sounds
長音
Long Vowels
Vowel lengthening (おう, こう, etc.)
+2
8 sounds
促音
Sokuon
Double consonant pause using small っ
+2
8 sounds