I have a question about using Independent Possessive Pronouns. Is it more normal to use 'das' with them regardless of the gender of the item, or should you use the correct definite article or pronoun? For example, I am in a waiting room, and someone is walking away leaving behind a pair of glasses (eine Brille). Which is better 'Ist das Ihre?' or 'Ist sie Ihre?'? Or at work and I locate a customer’s computer and I say ‘Ist das Ihrer?‘ or ‘Ist der Ihrer? What about plurals? Someone is looking for shoes: can I say ‘Ist das deine?’. I would really appreciate help.