- Prefixes: ག་ ད་ བ་ མ་ འ་
- Generally silent on their own
- Spelling recitation order: Prefix + “Oh” (འོག་) + Root Letter (etc.) = Complete Sound
- When there is a prefix, third column letters (ག་ཇ་ད་བ་ཛ་) lose aspiration and fourth column letters (ང་ཉ་ན་མ་ཡ་) gain high tone.