Turkish Vowel Harmony
There are two types of Vowel Harmony; Internal Vowel Harmony and External Vowel Harmony.
Internal Vowel Harmony is the harmony of all the vowel sounds inside a word.
In Turkish, a word can only have either Back or Front Vowels inside, both of them cannot be present inside a word. Some borrowed words that came into Turkish, may not follow this rule. Unless you’re a linguist, you don’t have to focus on Internal Vowel Harmony.
On the other hand, External Vowel Harmony is the most important topic you should master to understand the Turkish suffixation.
When we add a suffix to a word, we look at the last vowel in that word and choose the correct suffix option from the choices of that particular suffix.
Let’s look at an example suffix. The plural suffix in Turkish is the “-ler/-lar” suffix.
|a, ı, o ,u||Back||-lar||arkadaşlar, kızlar, turşular|
|e, i, ö, ü||Front||-ler||eller, işler, denizler|
Internal Vowel Harmony
Inside the External Vowel Harmony, we have the Two-Fold Vowel Harmony and Four-Fold Vowel Harmony.
The words Two-Fold and Four-Fold are used to show how many vowel variations a suffix has.
Because the Turkish plural suffix “-ler/-lar” has only two choices, it is a Two-Fold Vowel Harmony Suffix. We only need to focus on the Back or Front categorization to choose the correct choice.
With Four-Fold Vowel Harmony, we look at whether the last vowel is a Back or Front and a Rounded or an Unrounded vowel. Because of this, we have four suffix choices to choose from.
A good example would be the Third-Person Singular Possessive Suffix (also known as the Accusative Case Marker).
The “Third-Person Singular Possessive Suffix” is the “-ı, -u, -i, -ü” with the Buffer Letter “s”.
|a, ı||Back Unrounded||-(s)ı||arkadaşı|
|o ,u||Back Rounded||-(s)u||kutusu|
|e, i||Front Unrounded||-(s)i||evi|
|ö, ü||Front Rounded||-(s)ü||ütüsü|
When a word ends in a vowel, like the words “kutu” and “ütü”, we add the buffer letter “s” for this suffix.
Each Proper Noun may require a different Buffer Letter. Some pronouns don’t require any Buffer Letters.
There are some exceptions for certain borrowed words, where you have to use a Front Vowel suffix choice for a word ending with a Back Vowel.