extension String {
  func localized(from: String) -> String {
    return NSLocalizedString(self, tableName: from, value: self, comment: "")
  }

  func localizedFormat(from: String, _ arguments: CVarArg...) -> String {
    return String.localizedStringWithFormat(localized(from: from), arguments)
  }
}

let result2 = "total_word".localizedFormat(from: "MyLocalizable", 8)
// 200 233 989 words

let result2 = String.localizedStringWithFormat("total_word".localized(from: "MyLocalizable"), 8)
// 8 words