Since try is a transitive verb there is a receiver of the action.  Whether or not  it is expressed in the sentence by the infinitive phrase seems to be the question.  However, if someone came into your classroom and said, "Mary tried." or "Mary is trying."  The first question asked by the listener would be, Mary tried what?  The answer is to improve the condition of her house.

Therefore, it is clear that we have an infinitive noun phrase.  To place the phrase in the adverb block you would first have to guess what she is trying to accomplish.  

Mary tried gardening to improve her yard. (then this is adverbial)

Dan Phelan
www.academicvisions.com
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  ----- Original Message ----- 
  From: Sophie Johnson 
  To: [log in to unmask] 
  Sent: Friday, August 03, 2001 7:55 AM
  Subject: Re: <no subject>


  `Mary is trying to improve the condition of her house':

  There is no question in the above sentence of the verb's being anything more or less than `is trying to improve', nor of its object's being anything other than `the condition of the house'.  `Mary', the subject of this active-voice verb, is not acting upon `to improve the condition of her house'; she is acting upon `the condition of her house'.
   
  Analysis of this sentence must note that it contains an active-voice verb, and that the characteristic of an active-voice verb is that its subject acts upon its object: Its subject names its actor, and its object the acted-upon. `To improve the condition of her house' does not name the acted-upon. This sequence cannot, therefore, be the object of this sentence, direct or indirect. 

  This really is a very basic exercise in part-of-speech recognition.

  Sophie Johnson
  at ENGLISH  GRAMMAR TUTOR
  http://www.englishgrammartutor.com/
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    ----- Original Message ----- 
    From: Marylou Colucci 
    To: [log in to unmask] 
    Sent: Friday, August 03, 2001 12:18 PM
    Subject: Re: <no subject>


    to improve the condition of her house is an infinitive phrase that functions 
    as the direct object. 
    Mary is trying what? to improve the condition of her house