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Şehirde trafik nasıl(dır)? (in daily language you do not need -dır)

question meaning is already given with "nasıl, ne kadar, ne zaman, neden", so you never add the question suffix -mı, -mi.

Gramer hatamı/yanlışımı düzeltirseniz sevinirim!

(and the trafic in Istanbul is not very adopted to bikes. you can bike well in the islands of Istanbul or on the seashores.) 

Ne, Neden, Ne zaman, Ne kadar, Nasıl, Nerede, Nereye , Nereye, Kim, Kimi etc

if question word contains one of them it does not fisnish with "mi"

Nereye gittin ? where have you gone ?

Eve mi gittin ? Did you go to home ?

or eve gittin mi ? both are true "mi" must be after the word that is emphasized. for example

eve mi gittin ? hayır okula gittim.  no i went to school.

eve gittin mi ?hayır eve gitmedim. no i did not go to home . 

Adın ne ? What is your name ?

Adın Selim mi ?  İs your name Selim ?