He had to work all the time that he could.
请问这里的 that he could 是定语从句吧?这里为什么在 all the time 后面用 that 来引导定语从句呢?
根据英语语法,当 time 或 place 等名词后接限制性定语从句时,除通常用关系副词 when 或 where 外,有时也可以用 that 或省略关系副词,所以下面几句都可以:
He had to work all the time when he could.
He had to work all the time he could.
同意蒋老师的分析。网友想要语法书上的依据,我查到一处,参见Geoffrey Leech 等人写的
《朗文A-Z英语语法大全》: