This is the 12748th most frequent Korean word.
대형마트에서
"At a large mart/store."
The word '대형마트에서' indicates the location where the action of purchasing fruits happened.
대형마트에서 과일을 샀습니다.
I bought fruits at the large shopping mart.
Here, '대형마트에서' describes the location where the event is happening.
대형마트에서 행사가 진행 중입니다.
An event is taking place in the large shopping mart.
In this sentence, '대형마트에서' references the place where one can find products.