Learn Hardcore Turkish: Ödevimi tamamlayınca dinleniyorum.

The -ınca suffix turns a verb into a time-clause meaning “when/after ….” Here, tamamla- (to finish) + -ınca = “when/after I finish.” It’s a single suffix that covers both “when” and “as soon as.”

Why does ödevimi have two -i endings?

In ödevimi, the first -im is the 1st-person possessive (“my”) and the second -i is the accusative case marker for the direct object. Morphologically it’s ödev + -im + -i = “my homework” (as object).

What tense is dinleniyorum, and why use it here?

Dinleniyorum is the present-continuous form (root dinlen- + -iyor + -um). Although it literally means “I am resting,” in Turkish it often expresses habitual actions: “I rest (whenever I finish my homework).” You could also use the aorist dinlenirim for a general routine, but -iyor is very common for repeated actions.

Could we instead say Ödevimi tamamladıktan sonra dinleniyorum?

Yes. tamamladıktan sonra (“after having finished”) is another way to form the time-clause, using the verbal noun tamamlamak + -(d)ıktan sonra. It means the same as tamamlayınca, though -ınca is shorter and more colloquial.