难以

We gained a rich supply of data which would normally be inaccessible.

我们得到了通常难以获取的大量数据。

The horrors he experienced are imprinted, perhaps indelibly, in his brain.

他经历的恐怖事件在他脑海中刻下了深深的，或许是难以磨灭的印记。

What we need is not manifestos of pious intentions, but real action.

我们需要的不是善意但难以实现的宣言，而是实际行动。

Her aggressiveness made it difficult for him to explain his own feelings.

她咄咄逼人的态度让他难以解释自己的感情。

He was too inexperienced and too inexpert to succeed.

他太缺乏经验，太不熟练，难以成功。