本讲为2007年上半年新的教学内容，请对照教材及练习册听录音！
   
  Relative
  Relate
   
  I get up early so that I can catch up the first bus.
  I got up early this morning so that I caught up the first bus.
  ____ (exist)
   
  The relativity theory came into existence in the 20^th century.
  Twentieth
   

Affect    effect