Minimal Conditions: byle and byleby
To express a minimum requirement—meaning "provided that" or "as long as"—Polish uses the conjunctions byle and byleby. They are interchangeable, though byleby can feel slightly more emphatic.
When the condition applies to a general statement or shares the same subject as the main action, follow the conjunction directly with a verb in the infinitive.
| It is worth gathering forest mushrooms, provided you have a field guide. | Warto zbierać leśne grzyby, byle mieć atlas. |
| I will go to the forest, provided I find wild strawberries. | Pójdę do lasu, byleby znaleźć poziomki. |
Changing Subjects
When the condition introduces a new subject, the verb following byle or byleby must take the past tense form. Because these conjunctions trigger a subjunctive mood, you must use the past tense here even when referring to present or future events.
| A mushroom picker will eat anything, provided it is edible. | Grzybiarz zje wszystko, byleby to było jadalne. |
| I will make a soup, provided the mushrooms are edible. | Ugotuję zupę, byle grzyby były jadalne. |
| I will trust this mushroom picker, provided he knows what to gather. | Zaufam temu grzybiarzowi, byle wiedział, co zbierać. |
Negative Conditions
To express negative minimal conditions ("provided that not" or "as long as it doesn't"), simply place nie directly after the conjunction and before the verb.
| I will eat this wild plant, provided my stomach doesn't hurt. | Zjem tę dziką roślinę, byle nie bolał mnie brzuch. |
| Give these herbs to my brother, provided they are not poisonous. | Daj te zioła bratu, byle nie były trujące. |