I simply cannot understand what Wells thinks the greatness of a novel has to do with the length of the time he has spent reading it.

【翻译】我只是不明白，威尔斯认为的小说的伟大之处与他阅读小说的时间长短有什么关系。

【结构分析】

只分析宾语从句部分：what Wells thinks the greatness of a novel has to do with the length of the time he has spent reading it.  因为主谓部分很简单。

1. Wells thinks：“威尔斯认为”，插入语去掉。

what the greatness of a novel has to do with the length of the time he has spent reading it.

2. what是the greatness of a novel has to do的宾语。

3. do sth with...：与......有关。本句的sth. 就是what，意为“有什么关系”。

4. the length of the time：“时间的长度”，作with的宾语。

5. he has spent reading it：定语从句，修饰the time。