3.6 双重所有格
 
   物主代词不可与 a, an, this, that, these, those, some, any, several, no, each, every, such, another, which等词一起前置,修饰一个名词,而必须用双重所有格。
 公式为:
  a, an, this, that +名词+of +名词性物主代词。如:
    a friend of mine.
    each brother of his.