The Time Duration Suffix "-DIr" (For)
While you use the postposition beri to express that an action has been ongoing "since" a starting point, you use the suffix -DIr to express "for" a duration of time. It attaches directly to the time expression to show exactly how long a situation has been continuing up to the present.
Like most Turkish suffixes, it adjusts according to 4-way vowel harmony (-dır, -dir, -dur, -dür) and consonant mutation (-tır, -tir, -tur, -tür after voiceless consonants).
General and Plural Durations
You are not limited to exact numbers. You can attach this suffix to general phrases like uzun süre (a long time), or to plural time nouns to mean "for months" (aylardır), "for days" (günlerdir), or "for years" (yıllardır).
Asking Questions and Expressing Endurance
To ask questions like "for how many hours", simply attach the suffix to the time word following the question word kaç (how many), creating phrases like kaç saattir.
Because -DIr describes ongoing, persistent situations, it pairs frequently with verbs and adjectives about patience (sabırlı), endurance (dayanmak), or eventually giving up (pes etmek).
}