The Infinitive

Verbs in Turkish, when used alone, have the imperative meaning as in English.

do --> yap
come --> gel
go --> git
drink --> iç
sleep --> uyu

In order to make a verb infinitive, the suffix -mek is used.

to do --> yapmak (changes to -mak since yap[do] is a hard word)
to come --> gelmek
to go --> gitmek
to drink --> içmek
to sleep --> uyumak

The following are examples to the use of infinitives in Turkish:

It is good to sleep. --> Uyumak iyi(dir).
It is difficult to study. --> Çalışmak zor(dur).
I want to go. --> Gitmek istiyorum.
I want to walk. --> Yürümek istiyorum.



The Infinitive as an Object of a Verb

The Infinitive being a noun can take all the suffixes that any other noun takes - here we show the infinitive of some verbs in the Object case [suffix -i or -yi after a vowel] as an object of the main verb unutmak - to forget. We can also see that very often the main verb has two objects with the -i suffix. For instance in the last example below "The window " together with "its opening" are both in the Objective case of being ""forgotten.." as the main verb. If you inspect the other examples below you will see many double objects similarly.

Geçen hafta ödevimi yapmayı unuttum. - I forgot to do my homework last week.
Garajdan arabayı almayı unuttum. - I forgot to pick up (take) my car from the garage.
Ali, sana söylemeyi unuttu. - Ali forgot to tell you.
Affedersin, seni aramayı unuttuk. - We're sorry, We forgot to look (out) for you.
Filmi izlemeyi unuttum. - I forgot to watch the film.
Kediyi beslemeyi unuttum. - I forgot to feed the cat.
Mehmet'i sormayı unuttunuz - You forgot to ask Mehmet.
Kapıyı kapamayı unuttum. - I forgot to close the door.
Pencereyi açmayı unuttular. - They forgot to open the window.

About Verbal Objects

Some main verbs take Movement Towards suffix [-(y)e or -(y)a] as their objects i when the verb itself signifies movement towards. If we say in English - she is starting to write - then the Infinitive yazmak - to write - is the object of the verb - she is starting ... - and consequently must be suffixed to show its relationship to the verb. As the verb başlamak - to start, begin - signifies movement of some sort it governs the Movement Towards Condition in Turkish -a or -e. To effect the addition of the Movement Towards suffix to yazmak the final -k of -mek or -mak is dropped and the resulting verbal noun - yazma - is treated as a normal object by the addition of the Movement Towards Condition suffix -(y)a so yazmak - to write - becomes yazmaya başladı - she started to (to) write. It should be noted that we also use The Present Continuous Participle in -ing - (another noun) while translating in English so the above is often rendered in the following manner:
yazmak - to write - becomes yazmaya başladı - she started writing

Special Case - istemek - to want

The verb istemek - to want - is a special case as it causes no modification of the verb it governs:

yazmak istiyorum - I want to write
içmek isterler - they want to drink
kalmak istemedin - you didn't want to stay
çalışmak istemeyecekler - they will not want to work.
Note that this also applies in English - we also cannot say - I want writing - or - they want drinking.