主句和从句时态问题

Question

I would have failed but that you had helped me 和 I would have failed but that you helped me 哪句对

Answer 1

宾语从句可以遵循：主句用一般现在时,从句可以用任何时态. 主句用一般过去时,从句只能用过去时（如过去完成时、过去将来时等）主句用一般过去时,但如果从句是真理,只能用一般现在时。其它名词性从句,基本遵循上述。条件句 （1）真实条件句：主将从现（2）虚拟语气：与现在事实相反 主句：would / might...+ 动词原形 从句：一般过去时与过去事实相反 主句：would/ might ...+ have done 从句：had done 与将来事实相反 主句：would/ might...+ 动词原形 从句：一般过去时/ were to do / should do追问

I would have failed but that you had helped me所以这句是正确的？