英语翻译It is when he is on a scent and is not quite absolutely

英语翻译It is when he is on a scent and is not quite absolutely sure yet that it is the right one that he is most taciturn翻译 并解释一下这句话的结构.是福尔摩斯探案集里的句子 不过我好像隐约明白意思了 是个强调句，就是在当他有了一些线索，但是他又不太确定这些线索是正确的的时候，只有在这时候，他才会沉默寡言 （既当他一点没有线索时反而会说些话，会实事求是告诉人家，就是没线索） 整句结构就是 it is when .............that（这个that是right one后的that)he is most taciturn 基本这句话可以这样解释，就可能让结构看的更清楚：可以换个句子解释。it is when it is mornning that he will go out for some food只有在早晨的时候，他才会出去吃点东西 （既别的时间不去）或者是 it is when he is in a good mood that he will go out .......我怎么自己回答自己的问题了 哈哈