This is the 5642nd most frequent Turkish word.
paylaşmıştı
"Paylaşmıştı" means "he/she/it had shared" in English.
In this sentence, 'paylaşmıştı' refers to the act of having shared something (vacation photos) with friends in the past.
O sırada tatil fotoğraflarını arkadaşlarıyla paylaşmıştı.
At that time, he had shared vacation photos with his friends.
Here, 'paylaşmıştı' indicates that the sharing of the drawing on the social network occurred before referring to it in the past.
Dün yaptığı çizimi sosyal medyada paylaşmıştı.
She had shared the drawing she made yesterday on social media.
In the sentence, 'paylaşmıştı' conveys the notion of having told a secret to someone a long time ago, providing a past context.