what is it?
Turkish has two ways to express reciprocal actions — actions that two or more participants perform to or with each other. The first is the reciprocal suffix -(I)ş, which is added directly to a verb stem. The second is the pronoun «birbiri» («each other / one another»), which takes the normal case endings and works with any verb. The suffix -(I)ş is unproductive in modern Turkish: it exists only on a closed set of lexicalised verbs and cannot be freely attached to new stems. «birbiri» is the productive, general-purpose solution.
when to use it
Use a lexicalised -(I)ş verb when the verb you need already exists in that form. Common examples: öpüş- (kiss each other), görüş- (meet / see each other), dövüş- (fight each other), selamlaş- (greet each other), mektuplaş- (correspond with each other). These are single words; treat them as vocabulary items.
Use «birbiri» + case ending for any verb that does not have a lexicalised -(I)ş form, or when you want to make the reciprocal meaning explicit. The pronoun inflects for case just like a regular noun: birbirini (accusative), birbirine (dative), birbirinden (ablative), birbirinde (locative), birbirleriyle / birbirimizle (comitative, with person agreement).
Person agreement on «birbiri»: the stem «birbir-» takes a possessive suffix that matches the subject — birbirimiz (we … each other), birbiriniz (you pl. … each other), birbiri / birbirleri (they … each other). Case endings are added after the possessive suffix.
formation
The suffix -(I)ş follows four-way vowel harmony. It attaches to the bare verb stem, before tense/mood suffixes. Because the set of -(I)ş verbs is closed, the table below lists the most useful lexicalised forms rather than a productive rule.
| stem | reciprocal form | meaning |
|---|---|---|
| öp- | öpüş- | kiss each other |
| gör- | görüş- | meet / see each other |
| döv- | dövüş- | fight each other |
| selamla- | selamlaş- | greet each other |
| mektupla- | mektuplaş- | correspond with each other |
Note that «selamlaş-» and «mektuplaş-» end in -ş rather than «-ış / -iş / -uş / -üş» because the stem already ends in a vowel, so only «-ş» is added.
For «birbiri», the structure is: birbir- + possessive suffix + case suffix. The table below shows the most common combinations.
| person / number | dative | accusative | comitative |
|---|---|---|---|
| 1st pl. (biz) | birbirimize | birbirimizi | birbirimizle |
| 2nd pl. (siz) | birbirinize | birbirinizi | birbirinizle |
| 3rd pl. (onlar) | birbirine / birbirlerine | birbirini / birbirlerini | birbirleriyle |
examples in context
common pitfalls
Treating -(I)ş as productive. Learners sometimes try to add -(I)ş to any verb to create a reciprocal: ✗ yardımlaştık is not standard Turkish. If the verb does not already have a lexicalised -(I)ş form, use «birbiri»: ✓ birbirimize yardım ettik.
Doubling a reciprocal verb with «birbiri». When you use a lexicalised -(I)ş verb, do not also add «birbiri» — the reciprocal meaning is already encoded in the verb. ✗ Birbirlerini öpüştüler is redundant. Use either ✓ Öpüştüler or ✓ Birbirini öptüler.
Wrong case on «birbiri». «birbiri» must take the case that the verb requires, just like any noun. Common mistakes: using the bare form where a case suffix is needed (✗ birbiri yardım ettik), or mixing up dative and comitative (✗ birbirimize konuştuk instead of ✓ birbirimizle konuştuk). Always ask: which case does this verb take for its complement?