he must have had an accident,or he should have been here then.求详解

he must have had an accident,or he should have been here then.求详解
he must have had an accident,or he should have been here then.求详解

he must have had an accident,or he should have been here then.求详解
he must have had an accident,or he should have been here then
他一定出事故了,要不然他当时会在这儿了
语言点：
1.must have + 过去分词 这个结构用以对已经发生的事情作以肯定的推测,意为：想必已经.一定已经.
2.or 在此句相当于一个虚拟条件句.= If he had not had an accident
3.表示与过去事实相反,if 从句用had+ 过去分词（此句用or 表示了）,主句是：would/ should/ might/ could + have + 过去分词.此句是【should have been】