Is this the proper way to say "Sorry iv been busy"

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  JACKBOSMA July 7, 2016 at 3:23am

  ごめんなさい、私は忙しかったです。
  
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  JACKBOSMA July 7, 2016 at 3:27am

  わたしはいそがしかったです。
  
  
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  Ronin July 8, 2016 at 10:47pm

  Shouldn't that です instead be でした？ @JACKBOSMA
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  Acidron July 8, 2016 at 11:16pm

  @Ronin no, it's actually correct like that. 忙しいです=present tense,　いそがしかったです=i-adjective is conjugated into it's past form 忙しかった and desu is added. Good point to notice though, I was confused by this same thing once and surely other beginners will be too :)
• 
  mog86uk July 9, 2016 at 4:47am

  Or could use いそがしくありました instead of いそがしかったです.
  
  いそがしく + あり+まし+た
  　いそがしく is the adverbial conjugation of いそがしい.
  　あり is the infinitive form of ある "be".
  　まし is the infinitive form of the ます politeness auxiliary verb.
  　た is the perfect aspect / past tense auxiliary verb.
  
  いそがしく + あり+た + で + あり+ます
  　あり + た → あった is the perfect aspect / past tense form of ある "be".
  　いそがしく + あった → いそがしかった. The く 'ku' and あった 'atta' are combined into かった 'katta'.
  　です, at least in purpose, is the shortened form of で+あり+ます.
  　であります is the 'masu' polite form of である.
  
  いそがしかったです, as I've shown, essentially uses あり twice. The first time: to add た for past tense; the second time: to add ます for politeness.
  
  いそがしくありました only uses あり once, adding both ます and た all in one go in the form of まし(infinitive form of ます) + た = ました.
  
  But alas, いそがしかったです is by far the the normal one used in everyday polite speech. It's just that using です after an i-adjective seems pretty weird from a grammar perspective, even if it is standard.
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  mog86uk July 9, 2016 at 5:00am

  Oops. I think I got a bit carried away typing. Only meant to make a brief comment... But, before I knew it, it had turned into that crazy looking mess of a post...
  ^^;