code: func (mo *Mo) GetN(str, plural string, n int, vars ...interface{}) string {
  	// Sync read
  	mo.RLock()
  	defer mo.RUnlock()
  
  	if mo.translations != nil {
  		if _, ok := mo.translations[str]; ok {
  			return Printf(mo.translations[str].GetN(mo.pluralForm(n)), vars...)
  		}
  	}
  
  	if n == 1 {
  		return Printf(str, vars...)
  	}
  	return Printf(plural, vars...)
  }
docs: // GetN retrieves the (N)th plural form of Translation for the given string.
  // Supports optional parameters (vars... interface{}) to be inserted on the formatted string using the fmt.Printf syntax.