Vowel Harmony
Mongolian vowel harmony: back vowels (а, о, у) vs front vowels (э, ө, ү) determine suffix forms
Can identify back vs front vowel words and choose the correct suffix form
Look at these examples. Can you spot the grammar pattern?
Би гараас авлаа.
I took it from the hand.
Би өрөөнөөс гарлаа.
I left from the room.
Энэ ном сайн байна.
This book is good.
Pay attention to the highlighted parts. What do they have in common?
Vowel harmony means a word uses only one group of vowels, and suffixes must match.
| Group | Vowels | Suffix example |
|---|---|---|
| Back (masculine) | а, о, у | -аас, -аар, -тай |
| Front (feminine) | э, ө, ү | -ээс, -ээр, -тэй |
| Neutral | и | joins either group |
Rule: Look at the last vowel of the word to determine which suffix to use.
гар (hand) → гараас (from the hand) | өр (debt) → өрөөс (from the debt)
Common Error Patterns
Uses wrong suffix vowel group (e.g., -аас after front-vowel word)
Check the last non-neutral vowel in the word. Back (а/о/у) → back suffix; front (э/ө/ү) → front suffix.
Treats 'и' as determining suffix group
'и' is neutral — look at OTHER vowels in the word to determine the group.
Би гараас авлаа.
I took it from the hand.
'гар' (hand) has back vowel 'а', so ablative suffix is -аас (not -ээс).
Би өрөөнөөс гарлаа.
I left from the room.
'өрөө' (room) has front vowels ө/ө, so ablative is -нөөс (front suffix form).
Энэ ном сайн байна.
This book is good.
'ном' (book) has back vowel 'о'. Neutral 'и' in 'байна' joins back group here.
Practice in course
Apply this grammar in A1 course exercises