Questions & Answers about Dün parkta koşarken bileğim ağrıdı.
Parkta is park + -ta, the locative ending, meaning in the park or at the park.
- park = park
- -ta / -te / -da / -de = in / at / on, depending on vowel harmony and consonant voicing
Here, park ends in the voiceless consonant k, so the suffix appears as -ta rather than -da.
So:
- park = park
- parkta = in the park
Koşarken comes from the verb koşmak (to run).
It is built from the verb stem koş- plus -arken, which means while doing or when doing.
So:
- koşmak = to run
- koş- = run
- koşarken = while running
This form shows that one action was happening at the same time as another. In this sentence, the wrist started hurting during the time the speaker was running.