ruinami

In a sentence

• Spacerowaliśmy między ruinami zamku.

  We were walking among the ruins of the castle.

  In this sentence, "ruinami" is used to describe the remains of a castle, functioning as an instrumental plural form in a locative expression.

• Ruiny starożytnego miasta były imponujące.

  The ruins of the ancient city were impressive.

  Here, "ruiny" is a nominative plural form acting as the subject of the sentence, indicating the remnants of an ancient city.

• Pod ruinami budynku znaleziono stare artefakty.

  Old artifacts were found under the ruins of the building.

  In this case, "ruinami" is instrumental plural indicating the location under the debris or remains of a building.