第83课：Though a little suspicious this time,the policeman gave

第83课：Though a little suspicious this time,the policeman gave himthe same answer这是一个省略了
主语和连系动词的让步状语从句.通常,如果从句的主语与主句的相同而谓语带系动词be,则主语+be可省略（原因状语从句例外）：
原因状语从句的省略形式要带分词being：
Being worried about his child,he walked up and down in the room．
他由于为孩子担心,在屋子里来回走着.
但是：第49课第一句：
tired of sleeping on the flood,a young man saved up to buy a real bed .
此句中开头没保留 being 那么究竟原因状语从句是保留 being 还是不保留?