public function irregular($singular, $plural){
		Utils::array_delete($this->uncountables, $singular);
		Utils::array_delete($this->uncountables, $plural);
		
		$singular_char = substr($singular, 0, 1);
		$singular_char_upcase = strtoupper(substr($singular, 0, 1));
		$singular_char_downcase = strtolower(substr($singular, 0, 1));
		$singular_word = substr($singular, 1);
		
		$plural_char = substr($plural, 0, 1);
		$plural_char_upcase = strtoupper(substr($plural, 0, 1));
		$plural_char_downcase = strtolower(substr($plural, 0, 1));
		$plural_word = substr($plural, 1);
		
		
		if(strtoupper(substr($singular, 0, 1)) == strtoupper(substr($plural, 0, 1))){
			$this->plural("/({$singular_char}){$singular_word}$/i", '$1' . $plural_word);
			$this->plural("/({$plural_char}){$plural_word}$/i", '$1' . $plural_word);
			$this->singular("/({$plural_char}){$plural_word}$/i", '$1' . $singular_word);
		}else{
			$this->plural("/{$singular_char_upcase}(?i){$singular_word}$/", $plural_char_upcase . $plural_word);
			$this->plural("/{$singular_char_downcase}(?i){$singular_word}$/", $plural_char_downcase . $plural_word);
			$this->plural("/{$plural_char_upcase}(?i){$plural_word}$/", $plural_char_upcase . $plural_word);
			$this->plural("/{$plural_char_downcase}(?i){$plural_word}$/", $plural_char_downcase . $plural_word);
			$this->singular("/{$plural_char_upcase}(?i){$plural_word}$/", $singular_char_upcase . $singular_word);
			$this->singular("/{$plural_char_downcase}(?i){$plural_word}$/", $singular_char_downcase . $singular_word);
		}
	}