This is the 836th most frequent Turkish word.
yaptığını
"Yaptığını" means "what you did" or "what you have done" in English.
Here, 'yaptığını' is the noun-form conjugation of 'yapmak' (to do) in the accusative case, indicating the specific action being done.
Senin ne yaptığını bilmiyorum.
I don't know what you are doing.
In this sentence, 'yaptığını' refers to an indirect statement about the action 'Ebru completed' and functions in accordance with the accusative case.
Ebru'nun projeyi zamanında yaptığını söylediler.
They said that Ebru completed the project on time.
Here 'yaptığını' is used to express the accusative form of the verb 'yapmak' in a complex sentence to emphasize the object of the thought.