This is the 2236th most frequent Turkish word.
almıştı
"Almıştı" means "he/she/it had taken" in English.
In this sentence, 'almıştı' is used to denote a past perfect action, prior to another past reference point.
O, kitabı birkaç gün önce almıştı.
He had taken the book a few days ago.
Here, 'almıştı' conveys an action complete before the reported past thought.
O sırada herkes, onun zaten ödülü almıştı diye düşünüyordu.
At that time, everyone was thinking he had already received the award.
In this instance, 'almıştı' establishes a completed past action, adding context or background to the narrative.