correspondence  
noun uk/ˌkɒr.ɪˈspɒn.dəns/ us/ˌkɔːr.əˈspɑːn.dəns/
  (WRITING)         
  [ U ]信件,信函(尤指公函或商业信函) 
letters, especially official or business letters
  Any further correspondence should be sent to my new address. 以后来信请寄到我的新地址。 
  [ U ](尤指两个人之间的)通信,通信联系 
the action of writing, receiving, and reading letters, especially between two people
  Her correspondence with Jim lasted many years. 她和吉姆保持了多年的通信联系。 
   (MATCH)      
 [ C usually singular, U ](两个事物之间的)关联 
a connection between two things
  The survey found no correspondence between crime and unemployment rates. 调查发现犯罪与失业率之间没有关联。