这句话所包含的语法.
1.He had had a long and uncomfortable trip,for he had been confined to the wooden box for over eighteen hours.
2.He was so surprised at being discovered that he did not even try to run away.
我正在背新概念第2册 这2句是第46课中的,我很不理解had had ; had been; being discovered是什么语法 还有句中的一些词
had ;confined ;surprised ;discovered; did ;run 为什么都是过去时呢?
请您帮助我理解下以上两句话 .