Unless she had had an alarm clock, she would havemissed the train.(事实:她没有闹钟)中两个had是什么意思?

问题描述:

Unless she had had an alarm clock, she would havemissed the train.(事实:她没有闹钟)
中两个had是什么意思?

had had:第一个had是过去完成时的助动词,第二个had是have的过去分词.它们一起构成过去完成时.

条件句中用过去完成时,是对过去情况的虚拟语气,表示与过去事实相反的假设.

Unless she had had an alarm clock, she would have missed the train.
=If she had not had an alarm clock, she would have missed the train.

句意:如果她没有闹钟,她就已经错过了那列火车.
事实是:她有闹钟,所以她没有错过火车.

虚拟语气结构对过去的虚拟:had +动词过去分词
所以第一个had是助动词第二个是过去分词