Breakdown of Powinieneś był zareagować w rozsądny sposób.
być
to be
w
in / on (a day)
powinien
should, ought to
sposób
way, manner (w ten sposób)
Questions & Answers about Powinieneś był zareagować w rozsądny sposób.
Why does this sentence use powinieneś był instead of just powinieneś?
Adding the past tense marker był to powinieneś explicitly creates the meaning "you should have" (a past unfulfilled obligation). Without był, powinieneś technically means "you should" in the present or future, though native speakers often drop był in casual speech and rely on context.
Why is the personal ending -eś attached to powinien rather than był?
Why is the perfective verb zareagować used here rather than the imperfective reagować?
The speaker is referring to a specific, one-time past event where a reaction was needed. If the sentence were about a general past habit (for example, "You should have reacted reasonably every time they complained"), you would use the imperfective reagować.
What case is triggered by the preposition w in the phrase w rozsądny sposób?