Turkish endings are not irregular: they change vowel to match the word they attach to. Two-way endings take e after front vowels and a after back vowels. Four-way endings take i, ı, u or ü, copying both the position and the lip-rounding of the last vowel. Learn the two mappings and you can build forms nobody taught you.
Published 29 July 2026
Open any Turkish grammar and you will find endings listed in twos and fours. The plural is -ler or -lar. The word for "my" is -im, -ım, -um or -üm. It looks like the language is asking you to memorise four times as much as it should.
It is not. There is one plural ending and one "my" ending. What changes is the vowel inside them, and the vowel is not a choice — it is decided for you by the word the ending is attaching to. That is vowel harmony, and understanding it is the single biggest jump a Turkish beginner can make, because it converts a memorisation problem into a rule you apply.
Learn this properly and something unusual happens: you start producing correct Turkish forms you were never taught.
Turkish has eight vowels. To use harmony you need to know two things about each one: whether it is made towards the front or the back of the mouth, and whether your lips are rounded or relaxed when you say it.
| Unrounded (lips relaxed) | Rounded (lips pushed forward) | |
|---|---|---|
| Back vowels | a, ı | o, u |
| Front vowels | e, i | ö, ü |
Say a then e and feel your tongue move forward. Say i then ü and feel your lips round while your tongue stays put. Those two movements are the whole system. Everything below follows from this one table, so it is worth thirty seconds of actually saying them out loud rather than reading past it.
Some endings come in two versions, with e or a. The rule is front with front, back with back, and rounding is ignored entirely.
Look at the last vowel of the word. If it is a front vowel (e, i, ö, ü), the ending takes e. If it is a back vowel (a, ı, o, u), the ending takes a.
| Word | Last vowel | Plural | Meaning |
|---|---|---|---|
| ev | e — front | evler | houses |
| diş | i — front | dişler | teeth |
| göz | ö — front | gözler | eyes |
| gün | ü — front | günler | days |
| at | a — back | atlar | horses |
| kız | ı — back | kızlar | girls |
| kol | o — back | kollar | arms |
| okul | u — back | okullar | schools |
Eight words, one rule, no exceptions in that list. The dative ending (roughly "to") behaves the same way: ev becomes eve (to the house), okul becomes okula (to the school).
Other endings come in four versions — i, ı, u or ü. Here rounding matters as well as front and back, so the ending copies both properties of the last vowel.
The mapping is completely regular:
| If the last vowel is… | the ending takes… |
|---|---|
| e or i (front, unrounded) | i |
| a or ı (back, unrounded) | ı |
| ö or ü (front, rounded) | ü |
| o or u (back, rounded) | u |
Now watch the same eight words take the "my" ending:
| Word | Meaning | "My ___" |
|---|---|---|
| ev | house | evim |
| diş | tooth | dişim |
| at | horse | atım |
| kız | daughter | kızım |
| göz | eye | gözüm |
| gün | day | günüm |
| kol | arm | kolum |
| okul | school | okulum |
One ending. Four coats. The word chooses the coat.
Vowel harmony is not a rule somebody imposed on Turkish to make it tidy. It is what happens when a language builds long words by stacking endings: it is physically easier to keep your tongue in roughly one position across a long word than to jump it back and forth.
Say gözlerimizde ("in our eyes") and notice that every single vowel is a front vowel. Now say okullarımızda ("in our schools") and notice every vowel is a back vowel. The word is comfortable because it does not ask your mouth to change zones halfway through.
This is worth knowing because it gives you a check that does not require remembering any rule. If a Turkish word you have built mixes front and back vowels and it is not a compound or a loanword, it is very probably wrong — and you can hear that it is wrong before you can explain why.
Three groups genuinely break the pattern, and knowing them stops you concluding the rule is unreliable.
Borrowed words. Turkish has absorbed a great deal of vocabulary from Arabic, Persian and French, and many of those words do not harmonise internally — kitap, otobüs, televizyon. The rule still governs the endings you add to them, which is the part that matters to you. Kitap ends in a back vowel, so its plural is kitaplar.
A handful of loanwords take the "wrong" ending. Saat (hour, clock) looks like it should take -lar, but the plural is saatler. These are individual words to learn, not a pattern — there are not many and you will meet them naturally.
Some suffixes never change at all. The most important is -yor, the present-tense ending. It is always -yor, never -yör or -yar, which is why geliyor (he is coming) has a back vowel sitting in a front-vowel word. Treat it as a fixed block. More on it in the Turkish present tense.
Compounds do not harmonise across the join. Bugün ("today") is bu + gün, two words stuck together, so it is under no obligation to match itself.
Turkish does a smaller, similar thing with consonants, and it is worth recognising even if you do not drill it. An ending that begins with d switches to t after a voiceless consonant — the kind you make with breath rather than voice. So "in the school" is okulda, but "in the book" is kitapta, because p is voiceless. Same ending, adjusted to be sayable. It is the same instinct as vowel harmony applied to a different part of the mouth.
There is one plural ending, not two, and one "my" ending, not four. The last vowel of the word decides which coat the ending wears. Learn the two-way and four-way mappings and you can build forms nobody taught you.
Build the plural and the "my" form of each. All eight vowels are represented, and every one follows the rule.
Answers: (1) yollar, yolum — last vowel o, back and rounded. (2) şehirler, şehrim — the last vowel is i, front and unrounded, so the endings are front; note the middle vowel drops when a vowel-initial ending is added, which is a separate small pattern affecting a limited set of words. (3) kuşlar, kuşum — u, back and rounded. (4) köyler, köyüm — ö, front and rounded. (5) balıklar, balığım — ı, back and unrounded; the k softens to ğ between vowels, another small pattern worth meeting early.
If you got the vowels right in all five, harmony is working even where other patterns are also in play — and that is the point. Harmony is the layer underneath everything else.
Harmony decides the shape of every ending, so it comes before the endings themselves. Next is how Turkish stacks those endings in order, and then the six cases, which are simply the most useful endings to own first. If the vowels themselves are still shaky, go back to the alphabet — harmony is unusable until you can tell ı from i by ear.
Turkish is coming to Gora, where harmony is taught through words you are already using rather than as a table to memorise. See what is coming and join the launch list.