"Whose vegetables are these?"
Translation:Чиї це овочі?
They mean the same thing, but they differ in the grammatic structure. «Це» is a free-standing pronoun, while «ці» is a modifier to «овочі». Here's a graphical scheme:
- In Чиї це овочі? 'Whose vegetables are these?', це is a free-standing pronoun, the subject, and овочі is the predicate (чиї is the modifier for «овочі»).
- In Чиї ці овочі? 'Whose are these vegetables?', овочі is the subject (ці is the modifier of овочі), and чиї is the predicate.
The grammatical structure is a bit obscured because we move the question word to the beginning of the sentence.
Grammatically, «чиї» works as an adjective (however, it's not placed before noun because it is a question word and goes in the beginning). Like an adjective, it can:
- modify a noun (as in Чиї це овочі, it modifies овочі), or
- it can stand on its own (as in Чиї ці овочі?, it doesn't modify anything). You can think of it as of an adjective with a noun omited: Чиї ці овочі? = Чиї [овочі] ці овочі? 'Whose [vegetables] are these vegetables?'
I hope this explains why «Чиї це овочі» = 'Whose vegetables are these?', and «Чиї ці овочі» = 'Whose are these vegetables?".