public static function singularize(string $plural)
    {
        $pluralRev = strrev($plural);
        $lowerPluralRev = strtolower($pluralRev);
        $pluralLength = \strlen($lowerPluralRev);

        // Check if the word is one which is not inflected, return early if so
        if (\in_array($lowerPluralRev, self::$uninflected, true)) {
            return $plural;
        }

        // The outer loop iterates over the entries of the plural table
        // The inner loop $j iterates over the characters of the plural suffix
        // in the plural table to compare them with the characters of the actual
        // given plural suffix
        foreach (self::$pluralMap as $map) {
            $suffix = $map[0];
            $suffixLength = $map[1];
            $j = 0;

            // Compare characters in the plural table and of the suffix of the
            // given plural one by one
            while ($suffix[$j] === $lowerPluralRev[$j]) {
                // Let $j point to the next character
                ++$j;

                // Successfully compared the last character
                // Add an entry with the singular suffix to the singular array
                if ($j === $suffixLength) {
                    // Is there any character preceding the suffix in the plural string?
                    if ($j < $pluralLength) {
                        $nextIsVocal = false !== strpos('aeiou', $lowerPluralRev[$j]);

                        if (!$map[2] && $nextIsVocal) {
                            // suffix may not succeed a vocal but next char is one
                            break;
                        }

                        if (!$map[3] && !$nextIsVocal) {
                            // suffix may not succeed a consonant but next char is one
                            break;
                        }
                    }

                    $newBase = substr($plural, 0, $pluralLength - $suffixLength);
                    $newSuffix = $map[4];

                    // Check whether the first character in the plural suffix
                    // is uppercased. If yes, uppercase the first character in
                    // the singular suffix too
                    $firstUpper = ctype_upper($pluralRev[$j - 1]);

                    if (\is_array($newSuffix)) {
                        $singulars = [];

                        foreach ($newSuffix as $newSuffixEntry) {
                            $singulars[] = $newBase.($firstUpper ? ucfirst($newSuffixEntry) : $newSuffixEntry);
                        }

                        return $singulars;
                    }

                    return $newBase.($firstUpper ? ucfirst($newSuffix) : $newSuffix);
                }

                // Suffix is longer than word
                if ($j === $pluralLength) {
                    break;
                }
            }
        }

        // Assume that plural and singular is identical
        return $plural;
    }