This is the 1059th most frequent Russian word.
остались
"Остались" means "remained" or "stayed."
Here, 'остался' is used in the context of someone staying or remaining at a place.
Я остался дома, потому что почувствовал себя плохо.
I stayed at home because I felt unwell.
In this sentence, 'остались' indicates that some objects remained in a location after an event.
После вечеринки у нас остались кусочки торта.
After the party, pieces of cake remained with us.
Here, 'остались' is used to express the persistence or continuation of a situation, in this case, questions.