Translation:The girls had already returned from the party when you arrived.
The past participle of come is come, not came. It should be: the girls had already COME back
I thought the girls had "returned to the party" not "returned from the party". What is the difference?
Isn't the meaning here that: "The girls had already left the party when you arrived."
I think not, as I cannot find any suggestion in three dictionaries that voltar can mean to leave
Verbo ter é impessoal, e deve ser conjugado apenas na terceira pessoa do singular, independente do objeto direto estar no singular ou plural. (As meninas já tinha chegado...") The verb "ter" is impersonal, and must be conjugated only in the third person singular, independent of the direct object being in the singular or plural
It's impersonal only when it means "existir". Also, it is considered grammatically incorrect, since "Haver" should be used instead.
"As meninas já tinha chegado..." is grammatically incorrect.