The infinitive phrase "to improve the condition of her house"
can be substituted by the pronoun "it."  Thus, the infinitive
phrase is actually a NOUN PHRASE that functions
as the object of the verb "is trying."
  ----- 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