Questions & Answers about В какой бы город они ни переезжали, они не покидали нас.
Why is the verb переезжали in the past tense here?
The concessive construction [question word] + бы ни strictly requires the verb to be in the past tense, even if the overall meaning of the sentence applies to the present or future. In this specific sentence, the context is already in the past, but the past tense form is grammatically locked in by the particle бы regardless.
Why does the preposition в come at the very beginning of the sentence instead of right before the noun город?
In Russian, when an interrogative word like какой modifies a noun and is used with a preposition, the preposition must come before the interrogative word. You must say В какой бы город (literally 'Into which would city') rather than putting в right before город.
Since they actually did move to these cities, why is the negative particle ни used before переезжали?
In this specific grammar pattern, ни does not negate the verb. Together, the question word (какой), the particle бы, and the particle ни create the universal meaning of 'no matter which' or 'whatever'. If you accidentally used не, you would change the meaning to a literal negation, implying they did not move.
Why are both переезжали and покидали in the imperfective aspect?