For example, let's say I work a job I hate and find it unpleasurable.

比如说，我做着一份自己讨厌的工作，并且觉得不愉快。

He was young still, and in a few years he would look back on all his misery with a sadness in which there would be something not unpleasurable.

他年纪还很轻，几年以后再回顾这一段惨痛遭遇，在悲痛中或许不无某种愉悦的感觉。