Isaac had found the work unendurable and walked out of the job.

艾萨克觉得这份工作实在令人难以忍受，就辞职走人了。

He had not expected the pain to be unendurable.

他没料到会如此疼痛难忍。

It has placed an almost unendurable strain on their marriage.

这给他们的婚姻带来了几乎难以承受的压力。