Breakdown of Каждый человек мечтает о своём пространстве.
человек
person
о
about (о, об, обо)
мечтать
to dream
каждый
every
Questions & Answers about Каждый человек мечтает о своём пространстве.
Why do we use своём here instead of его?
The reflexive possessive pronoun свой is used because it reflects back to the subject of the sentence, человек. If we used его, it would imply that every person is dreaming about some other specific man's space. Whenever the owner of the object is also the subject of the sentence, you must use a form of свой.
What case is своём in this sentence?
It is in the Prepositional case. The preposition о requires the Prepositional case here. Because свой acts like an adjective, it has to match the noun it describes in gender, number, and case. Since пространство is a neuter singular noun, its Prepositional form is пространстве, and the matching pronoun is своём.
Does the verb мечтать always take the preposition о?
Yes, when you are talking about what someone is dreaming of or wishing for, the verb мечтать always pairs with the preposition о (or об before a vowel sound) followed by the Prepositional case.
The English translation says 'their own space', but isn't своём singular here?
That is right! In Russian, каждый человек (every person) is grammatically a singular subject, so it is treated as a singular owner. English often uses the singular 'their' to be gender-neutral, but Russian handles this simply by following the singular grammar of the word человек.