Tüketim dönemi otuz gündür.

The consumption period is thirty days.

Breakdown of Tüketim dönemi otuz gündür.

• gün: the day
• otuz: thirty
• tüketim dönemi: the consumption period

Questions & Answers about Tüketim dönemi otuz gündür.

Why is it dönemi and not dönem? Is that -i the accusative ending?

No. Here, -i is not the accusative ending.

Tüketim dönemi is a very common Turkish structure called an indefinite noun compound. In this pattern:

• the first noun stays plain: tüketim = consumption
• the second noun takes a 3rd-person possessive ending: dönem-i

So tüketim dönemi means consumption period.

Similar examples:

• yaz tatili = summer holiday
• öğrenci kartı = student card
• otobüs durağı = bus stop

So the -i in dönemi is part of the compound, not an object marker.

Why is there no separate word for is in this sentence?

Because Turkish often does not use a separate present-tense verb to be in the 3rd person.

In English, you need is:

• The consumption period is thirty days.

In Turkish, a noun or noun phrase can act as the predicate by itself:

• Tüketim dönemi otuz gün.

So Turkish does not need a separate word equivalent to English is here.

Then what exactly does -dür do in gündür?