Learn Turkish: Spot oyuncuyu aydınlattığında büyük bir alkış duyduk. - When the spotlight illuminated the actor, we heard a great applause.

The root is aydınlat- (to illuminate). We add -tık (a variant of the -dık suffix, changing because aydınlat- ends in a hard consonant). Next comes the 3rd-person possessive -ı because the spotlight is doing the action. This suffix softens the k to ğ. Finally, we add the buffer -n- and the locative suffix -da ("at the time of"). Result: aydınlat + tığ + ı + n + da.

Why does oyuncu take the accusative suffix here (oyuncuyu)?

It is the specific direct object of the verb aydınlattığında. Because the spotlight illuminated a specific actor ("the actor"), it needs the accusative case. We add the buffer -y- and the suffix -u to match the vowels in oyuncu.

Why is the word order büyük bir alkış instead of bir büyük alkış?

In Turkish, when an adjective modifies a noun with the indefinite article bir (a/an), bir almost always goes between the adjective and the noun. It literally translates to "great a applause".

What is the base word for the verb aydınlattığında?