极难的英文：
hardest

A fiendishly difficult puzzle
极难解开的谜

Hope is a very unruly emotion. —— Gloria Steinem
希望是一种极难控制的激情。——斯坦内姆

graphite and even its linear counterpart, poly(p-phenylene) are too insoluble
石墨甚至其线性类似物，聚(名聚-苯撑)都是极难溶解的。

The first step is the hardest
万事开头难

Silence is one of the hardest arguments to refute.
沉默是最难反驳的论点之一。

Silence is one of the hardest arguments to refute
沉默是最难反驳的论点之一

The hardest work was assigned to the strongest laborers.
最繁重的工作分配给最强壮的劳工。

Topaz is one of the hardest gem minerals.
黄水晶是非常坚硬的宝石矿中的一种。