1- Ne kadar zamandır İstanbul'dasın? 2-Ne kadar zamandır Türkçe öğreniyorsun?

5) causative -t and -dir are the causative suffixes. As quantity, -dir is used much more. Of course it's not irregular, it has definite rules but no need to explain all them now. ölmek: to die öldürmek: to kill (öl + dür + mek) kanmak: to easily trust something/someone wrong. kandırmak: to convince someone for some wrong purpose (kan + dır + mak) bilmek: to know bildirmek: to inform, to report (bil + dir + mek) etc. 6) since you can't use it on the definite dates. it's wrong to say "2000'dir" when you want to mean "since 2000". it's wrong to say "Çarşamba'dır" when you want to mean "since Wednesday" it's wrong to say "hafta sonudur" when you want to mean "since the weekend". you must use it on the expressions of durations. üç yıl: three years üç yıldır: for three years (lit. : since three years) (started three years ago and still the present) Üç yıldır yurt dışına gitmedim. (I haven't been abroad for three years.) means: you last visited abroad three years ago. birkaç ay: several months birkaç aydır: for several months Birkaç aydır Facebook'a girmiyorum. (I haven't been logging in Facebook for several months.) means: you were last online several months ago. dokuz gün: nine days dokuz gündür: for nine days Dokuz gündür buradayız. (We are here/we have been here for nine days.) means: you came here nine days ago and you are still here. ne kadar: how much ne kadar zaman: how much time -> how long Ne kadar zamandır İstanbul'dasın? Ne zamandır İstanbul'dasın? Kaç zamandır İstanbul'dasın? How long have you been İstanbul? means: You are in İstanbul now and I ask about the time elapsed since you came. It may seem complicated because one can't colour the words in this question-answer section.

the suffix -dir has many tasks. 1) official/formal speech Türkiye'nin başkenti Ankara. The capital of Turkey is Ankara. Türkiye'nin başkenti Ankara'dır. The capital of Turkey is Ankara'dır. (official speech) 2) generalisation Gül de bir çiçek. Rose is a flower, too. Gül de bir çiçektir. (as an unchangeable truth) rose is a flower, too. Para kazanmadan büyük şehirde yaşamak zor. It's difficult to live in a big city without earning money. Para olmadan büyük şehirde yaşamak zordur. It's difficult to live in a big city without earning money and this can never be denied. 3) guess +Çocuk nerede? (Where is the child?) -Bahçede. (He/she is in the garden.) -Bahçededir. (He/she may be in the garden.) Acaba bu adam kaç yaşında. (I wonder how old this man is.) Acaba bu adam kaç yaşındadır. (I wonder how old this man is.) Both mean the same but, in the second sentence, the meaning of doubtfulness is more emphasised in comparison with the other one. 4) examplify Pek çok öğrenci, Fransa'dır, İngiltere'dir, Almanya'dır, İtalya'dır, Amerika'dır, gelişmiş ülkelerde okumak istiyor. Pek çok öğrenci Fransa, İngiltere, Almanya, İtalya, Amerika gibi gelişmiş ülkelerde okumak istiyor. A lot of students want to study in the developed countries such as France, England, Germany, Italy, USA.