请帮忙分析动词不定式和被动语态的两道题

1.______with the new method,the material does not break up easily.
A.To have treated B.Having treated C.Being treated D.Having been treated
选D,意思是,"被新方法处理了之后,这种材料不会很容易就坏了".对于材料来说,是"被处理",被动的只有C和D,而根据题目意思,是处理好以后,所以用现在完成时的被动D.
2.When they met,Leonardo and his enemy were fighting_______.
A.killed each other B.killing each other C.to be killed each other D.to kill each other
句意是"当他们相见的时候,里昂纳多和他的对手都争斗以致于互相残杀",表示打斗的目的是互相残杀,用不定式表示目的,所以选D.