Hi , thank you for helping us so much it's so useful

regarding the subject (infinitives) can you explain to me whats the meaning of dir and why you added it?

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

It is good to sleep. --> Uyumak iyi(dir).

thanks and best regards

Anood

The 'dir' suffıx ıs the personal endıng of the 3 rd person sıngular for the complıment 'To be' present tense :
'he/ she / ıt' IS
It can take 4 forms accordıng to vowel harmony
'dir/dır/dur/dür '
and also can take 'hard forms'
'tir/tır/tur/tür

But ıts usage ıs OPTIONAL
you can say eıther
'iyiDİR'
OR
'iyi ' and ıt both cases ıt would beam 'It ıs good'
More examples
'kırmızıDIR
Kırmızı = both means 'IT IS red'
greetıngs!

the "dir/dur/ tir/tur" is optional for the third person singuar, like Dilara explained.
still I have learnt that it is used for the third person singular when you want to underline what you are saying

eg: "bos yer yoktur"= there are no empty places
"bu yol kapalidir"= this road is close
"cocuklar icin degildir"= it is not (recommended) for the kids

Or for Tahmin 'guessing',that you are guessing,maybe almost sure,but you didn't see for yourself.

Eminim,şimdi Kerem,ve Gönül kütüphanede ders çalışıyorDUR.
İ'm sure,now Kerem and Gönğl are in the library studing the lesson.

You are sure,because they are in the library,but you didn't see for yourself,you are guessing that what they must be doing in there.

Döyle lüks bir arabanın sahibi mutlaka çok zenginDİR.
You don't know for sure that he is rich,you don't know him,but you see a very luxury car,and you by there are guessing its owener must be rich.

And DIR can be used to express formal speaking too.

Thnaks guys for helping :*
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