情态动词后,一般只能用动词原形.如：He can achieve a high mark if he takes the teacher's advice.
如果说他过去没有接受老师的建议,且没有取得高分,此时就可以很惋惜地说：If he had take the teacher's advice,he would have achieved a higher mark.
除了would have done,还有could have done 和might have done等形式,并没有would had done 这种说法.
希望能够帮到你,祝你学习愉快!