Explanation

“Piteously” is the clue for the first blank. Bleated is used metaphorically here — to bleat is to make the weak, wavering cry of a sheep, goat, or calf. Basically, saying that someone is bleating is calling his complaints pathetic, which matches with the clue “piteously,” as well as the later “bemoan.”

The part of the sentence after the semicolon matches the first part in structure — the second blank parallels “wealthy business leaders,” and the third mirrors “corrupt the youth” (turpitude is “depravity or immorality”).

Bleated, oligarchy, turpitude.