Breakdown of Przeprowadzka to moment, kiedy wszystko jest w pudełkach.
być
to be
w
in / on (a day)
to
is (linking copula)
kiedy
when
Questions & Answers about Przeprowadzka to moment, kiedy wszystko jest w pudełkach.
How does kiedy work in this sentence? Is it asking a question?
No, here kiedy (when) isn't a question word. It is acting as a relative pronoun. It links the noun moment to a descriptive clause, telling us exactly what kind of moment moving house is. It works exactly like "when" in the English translation!
Why does the sentence use to instead of jest for "Moving house is a moment"?
In Polish, when you are defining one noun with another noun (Noun A is Noun B), you typically use to. Here, the noun przeprowadzka (moving house) is being defined as the noun moment. If you used the verb być (to be) directly, you would need the Instrumental case: Przeprowadzka jest momentem. Using to lets you keep both nouns in their basic dictionary form (the Nominative case).
What case is w pudełkach and what is its base form?
It is in the Locative case, which is required after the preposition w (in) when expressing a location. The base noun is pudełko (box), which is neuter. The regular Locative plural ending for nouns is -ach, giving us w pudełkach (in boxes).
Why does wszystko (everything) take the singular verb jest?