Questions & Answers about Я хочу купить то платье.
Why do we use купить here instead of покупать?
купить is the perfective verb, meaning it focuses on a single, completed result. You use it here because you want to complete the action of buying one specific dress. If you were talking about buying dresses in general or as a habit, you would use the imperfective verb покупать.
Is платье in the accusative case since it is being bought?
Yes! It is the direct object of the verb купить, so it is in the accusative case. But because платье is a neuter noun, its accusative form looks exactly the same as its dictionary (nominative) form.
Why is the word for 'that' то instead of тот or та?
The word for 'that' has to match the gender and case of the noun it describes. Since платье is a neuter noun in the accusative case, we use the neuter accusative form то. тот is for masculine nouns, and та is for feminine nouns.
How is то different from это?
это means 'this' (something close to you), while то means 'that' (something further away). If you were holding the dress, you would say это платье (this dress), but if you are pointing to it across the store, you say то платье (that dress).