Learn Turkish: Çocuk koltuğun arkasında oturuyor. - The child is sitting behind the armchair.

In Turkish, spatial words act like nouns. Arka means "back". To say "behind", you literally say "at its back". We add the possessive suffix -sı ("its"), a buffer letter -n-, and the locative suffix -da ("at"). Put together, arka-sı-n-da means "at the back of" or "behind".

Why is the word for armchair koltuğun here instead of just koltuk?

Because we are literally saying "at the back of the armchair". This requires a possessive relationship to link the objects. The "owner" of the back (the armchair) needs the genitive suffix -un (meaning "of"), which turns it into koltuğun.

Where did the ğ in koltuğun come from?

The base word is koltuk. When a Turkish word ends in -k and we add a suffix starting with a vowel (like the -un suffix here), the -k softens into a "soft g" (ğ). This is a common rule called consonant mutation that makes the word smoother to pronounce.

Why do we use the continuous tense oturuyor instead of just saying the child "is" there?