Faced with unethical demands, he would sooner quit his job than violate his moral code.

would 是助动词 will 的过去式,本身可表示意愿、习惯、假设等含义,在 would sooner 短语中与 sooner 一起共同表示"宁愿"的意思,并不单独表示"宁愿"。 sooner 是 soon 的比较级形式,字面意思是"更快、更早",但在 would sooner 短语中已虚化为固定搭配的一部分,整体表示"宁愿"。 would sooner 是固定搭配,后接动词原形,后跟 than 引出对比项,意思是"宁愿...也不愿...",用来表达在两个选项中更倾向于前者。