This is the 2615th most frequent Turkish word.
tamamlanması
The completion of something.
In this sentence, 'tamamlanması' refers to the 'completion' and specifies the process of the project being finished.
Projenin tamamlanması için ekip çok çalışıyor.
The team is working hard for the completion of the project.
Here, 'tamamlanması' denotes the state of the task being brought to conclusion.
Bu işin tamamlanması zaman alacak gibi görünüyor.
It seems that the completion of this task will take time.
'Tamamlanması' in this context indicates the end state of the buildings after they are completed.