He _____(run after ……quickly) the thief but he couldn't catch him .解释句意并说明理由
问题描述：
He _____(run after ……quickly) the thief but he couldn't catch him .解释句意并说明理由
答
He quickly ran after the thief but he couldn't catch him.
but连接并列成分.he couldn't 是can't的过去式形式所以前边也用过去式ran.