src/locale/RU.js
function pluralize(number, words) {
  var magnitude = number % 100;
  var pluralWord = ''

  if ((magnitude > 10 && magnitude < 20) || (number === 0)) {
    pluralWord = words[2];
  } else {
    switch (Math.abs(number % 10)) {
      case 1:
        pluralWord = words[0];
        break
      case 2:
      case 3:
      case 4:
        pluralWord = words[1];
        break
      default:
        pluralWord = words[2];
        break
    }
  }
  return [number, pluralWord].join(' ')
}
function pluralize(number, words) {
  var magnitude = number % 100;
  var pluralWord = ''

  if ((magnitude > 10 && magnitude < 20) || (number === 0)) {
    pluralWord = words[2];
  } else {
    switch (Math.abs(number % 10)) {
      case 1:
        pluralWord = words[0];
        break
      case 2:
      case 3:
      case 4:
        pluralWord = words[1];
        break
      default:
        pluralWord = words[2];
        break
    }
  }
  return [number, pluralWord].join(' ')
}
For example:
1 год
2 года, 3 года, 4 года
5 лет, 6 лет … 11 лет, 12 лет … 20 лет
21 год, 31 год
22 года, 32 года
@param {number} number
@param {Array} words
@return {string}