Of course everyone else knew but I heard it for the first time.

Thanks, tunci. Go to sleep.

3 rd person singular does not take a suffix

As in

İyiym

İyin

İyi...not iyidir ´grammatically but you can hear it used in daily speech´

´´´The -dir has more to do with generalisation, building statements based on common facts and swiching from personal voice to common voice. ´´´

Yolla , there are missing letters in ;

[Ben] iyiyim --> I am fine [good]

[Sen] İyisin ---> You are fine [good]

[O] İyi  ---> He/She/It is fine [good]

Thank you , It was a copied text but my intention was to point out to " dir " matter ( the red highlighted text ) , i didnt notice these mistakes .