极难的 meaning in English

murderous

" with the new judging system , " says weir , " the spins are very difficult . you need a strong core to pull yourself into crazy positions .
在新规则下，旋转变得非常难。拥有强健的腹肌才能完成各种极难的姿势。
I ' m afraid your research targets a very difficult question , and that ' s the question of happiness , is it easy for you to define this notion or attitude very easily
我认为您的研究中所面对的是一个极难的问题，也就是幸福与否的问题。我想问，对您来说，解释幸福容易吗？