Pluralizable messages are defined as follows:

English:

message: !!pl
  0: No fools.
  1: One fool.
  n: %d fools.

Defaulting sequence: (0, 1) => n

Russian:

message: !!pl
  0: Дураков нет.
  1: %d дурак.
  2: %d дурака.
  n: %d дураков.

Defaulting sequence: (0, 1, 2) => n