Conjunctions
Common Polish conjunctions include i (and less commonly oraz) meaning "and", lub and albo meaning "or", ale meaning "but", lecz meaning "but" chiefly in phrases of the type "not x but y", że (or more formally sometimes iż) meaning "that", jeśli meaning "if" (also gdyby, where by is the conditional particle), czy meaning "whether" (also an interrogative particle), kiedy or gdy meaning "when", więc, dlatego and zatem meaning "so, therefore", ponieważ meaning "because", choć/chociaż meaning "although", and aby/żeby meaning "in order to/that" (can be followed by an infinitive phrase, or by a sentence in the past tense; in the latter case the by of the conjunction is in fact the conditional particle and takes personal endings as appropriate).
In written Polish, subordinate clauses are normally set off with commas. Commas are not normally used before conjunctions meaning "and" or "or".
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