have done和had done的区别|
  • have done和had done的区别|
  • have done和had done的区别have done和had done的区别是:have done是现在完成时。现在完成时表示的是处...

    have to与must的区别|
  • have to与must的区别|
  • have to与must的区别must与have to都有"必须、应该"的意思。但二者有区别:1) must侧重于个人意志和主观...