The Co-operative form of the verb is where the sense given is that the action is performed with another person or persons. The co-operation may be contrary in meaning. - ie. They fought EACH OTHER. In this case Turkish will use its co-operative form of the verb vuruşmak - meaning - to fight EACH OTHER - as opposed to the basic verb - vurmak - to hit. - Many commonly daily used words are of the Co-operative form, and as we learn them we may not realize this.
In English it is not always apparent when a verb is co-operative, for instance the verb to collide. You can collide with a wall - (a single occurrence) or with another car - (co-operative occurrence). Turkish does make this distinction:
In the first case: - çarpmak - to bump, collide
Bir duvara çarptım - I bumped a wall
In the second case: - çarpışmak - to bump, collide with.
Bir arabayla çarpıştım. - I collided with a car
The Co-operative verb sign is -iş which is added to the verb stem and it is subject to Vowel harmony so the suffix can take the following forms: -ış or -iş or -uş or -üş and -ş is added to verb stems which end in a vowel.
| Active Verb | Co-operative Verb |
|---|---|
| vurmak - to hit ona vurdum - I hit him | vuruşmak - to hit Birbirleriyle vuruştular - They fought each other. [Lit: hit each other] |
| görmek - to see Memet'i gördüm - I saw Mehmet | görüşmek - to see each other/to meet Mehmet ile görüşeceğim - I'm going to meet Mehmet [Lit: I will meet (see each other) with Mehmet.] |
| anlamak - to understand Ali'yi anlıyoruz - We understand Ali | anlaşmak - to understand each other/to agree Anlaşıyoruz, değil mi? - We agree, don't we? Ali ile anlaşıyoruz. - We agree with Ali. [Lit: understand each other] |
| Birbirleriyle - with each other - We should use always - ile - with - with co-operative verbs, since the action is done by at least two persons. | |
As we mentioned in the heading of this section many Co-operative forms are in regular use and one should begin to get the feeling in Turkish that the -iş suffix concerns something that is done in concert (either with or against.) - and can be used with certain nouns to show "a doing together".
This "in concert" suffix also shows up in some nouns - for instance - giriş - means - entrance - but can be construed to mean - [Lit: - an entering in concert].
Similarly - çıkış - exit - [Lit: - a leaving in concert]
Also as previously mentioned many verbs with regular use are in the Co-operative form:
anlaşmak - to agree - [to understand together]
sevişmek - to make love - [with each other]
öpüşmek - to kiss - [with each other]
Although konuşmak - to speak - [with each other] and çalışmak - to work - [with or at something or other] are not really co-operative verbs we can see that -iş- shows that these verbs show "a doing together"