新概念英语二册第49课,Tired of sleeping on the floor,a you...
新概念英语二册第49课,Tired of sleeping on the floor,a you... 新概念英语二册第49课, Tired of sleeping on the floor,a young man in Teheran saved up for years to buy a real bed.书上说,tired引导的分词短语省略了开头的being,其作用相当于原因状语从句:As he was tired of...,我不知道在什么情况下能有这种用法,是不是原因状语从句的引导词中都有这种用法?