Is this the novel()you bought yesterday?

1.that 2 the one
你可以这样看：
第一句用陈述句语气为：this is the novel that you bought yesterday.
这个句子主体结构是主语+谓语+系动词,指示代词this作为主语,is为谓语,the novel 为表语,that you bought yesterday 是限制性定语从句,修饰the novel,that是关系代词
第二句改为陈述语气为：This novel is the one you bought yesterday
这个句子主体结构也是主语（the novel）+谓语（is）+表语（the one）,后面的you bought yesterday 实际上是省略了关系代词的限制性定语从句,
实际上应为：This novel is the one （that/which）you bought yesterday.
因为先行词 the one 在从句“you bought yesterday中充当宾语,故关系代词that/which 可以省略,这是英语中约定俗成的.
以后碰到这种题目,你把句子改为正常语序,即换成陈述句语序,这样就一目了然了
这也是这种题目考查的意图所在

1 the one 特指的某一物品！
2 that 因为其在从句中作宾语，而且其主语是物，而非人！