We all like the book whose writer/the writer of which/ of which the writer is HanHan .
We all like the book whose writer is Hanhan
We all like the book the writer of which is Hanhan
We all like the book of which the writer is Hanhan
关系代词whose+名词 引导的定语从句可转化为 the+名词+of+ which / whom 或 of+ which/whom+ the +名词结构；of 表所属关系.
【例】I live in a room whose windows are all broken.
=I live in a room of which the windows are all broken.
= I live in a room the windows of which are all broken.
【例】This is my teacher whose handwriting is excellent.
= This is my teacher the handwriting of whom is excellent.
= This is my teacher of whom the handwriting is excellent.