function howManyTimesBetween(string $sentence): string
{
    $errorMessage = 'Your question is strange';
  
    $datesString = explode(' and ', $sentence);
  
    if (count($datesString) !== 2) {
      return $errorMessage;
    }
  
    $date1 = DateTime::createFromFormat('Y-m-d', $datesString[0]);
    $date2 = DateTime::createFromFormat('Y-m-d', $datesString[1]);
  
    if ($date1 === false or $date2 === false) {
        return $errorMessage;
    }
  
    $diffStrings = [];
  
    if ($date1 == $date2) {
        return 'Dates are equals';
    }
  
    $diff = $date1->diff($date2);
    
    if ($diff->y) {
        $diffStrings[] = $diff->y.' year(s)';
    }
    
    if ($diff->m) {
        $diffStrings[] = $diff->m.' month(s)';
    }
    
    if ($diff->d) {
        $diffStrings[] = $diff->d.' day(s)';
    }
  
    if( ($diff->y && $diff->m) || $diff->m) return 'There are '.implode(', ', $diffStrings).' between '.$sentence;
    elseif($diff->d) return "There are ".$diff->d." day(s) between ".$sentence;
}