When describing a person's transformation or a shift in their social standing, Polish uses verbs like stać się (to become) and okazać się (to turn out to be). The outcome or resulting identity always takes the Instrumental case.
Becoming
The verb stać się is perfective, describing a completed transformation. To form the Instrumental case for most masculine and neuter nouns, add the ending -em.
| Before he left, he became a bankrupt. | Zanim wyjechał, stał się bankrutem. |
| This young politician quickly became a careerist. | Ten młody polityk szybko stał się karierowiczem. |
For an ongoing process, use the imperfective stawać się (to be becoming). Remember that feminine nouns take the Instrumental ending -ą. Neuter nouns take -em (spelled -iem after k or g, as in pośmiewisko → pośmiewiskiem).
| She used to be an icon, and now she is becoming a laughing stock. | Kiedyś była ikoną, a teraz staje się pośmiewiskiem. |
Turning Out to Be
To express that someone "turned out to be" something, use okazać się (perfective) or okazywać się (imperfective). Just like verbs of becoming, these require the Instrumental case.
Pay special attention to masculine nouns ending in -a, such as kłamca (liar) and skandalista (scandalmonger). Even though they describe men, they decline like feminine nouns and take the Instrumental ending -ą. Notice the difference below between the "feminine-like" kłamcą and the standard masculine oszustem:
| Before he disappeared, this famous leader turned out to be a liar and a fraud. | Zanim zniknął, ten znany lider okazał się kłamcą i oszustem. |
Keep in mind that you only need the Instrumental case when these specific verbs drive the sentence. Exclamations like co za (what a...) leave the noun in the basic Nominative case, while the outcome verb takes the Instrumental:
| What a liar! He turned out to be a laughing stock in front of the whole company. | Co za kłamca! Okazał się pośmiewiskiem przed całą firmą. |