Complex sentence: When Eglė discovers that her beloved is dead, as a punishment for betrayal she turns her children and herself into trees-the sons into strong trees, an oak, an ash and a birch, whereas the daughter was turned into a quaking aspen.
Split into simpler sentences: When Eglė discovers that her beloved is dead, as a punishment for betrayal she turns her children and herself into trees. The sons were turned into strong trees, an oak, ash and birch, whereas the daughter was turned into a quaking aspen.