title: Program to remove proper nouns from paragraph
body: <p>I am attempting to write a program that removes all the proper nouns from a paragraph that is parsed from Wikipedia.</p>
  
  <pre><code>no_pnoun_paragraph = ""
  for i in range(len(clean_paragraph)):
    if clean_paragraph[i].isupper() == True and clean_paragraph[i - 2] != ".":
     cutoff = clean_paragraph[i:]
     delete = cutoff[:cutoff.find(" ")]
     clean_paragraph = clean_paragraph.replace(delete, "")
  print clean_paragraph
  </code></pre>
  
  <p>This attempts to remove all the words that start with an uppercase letter but do not begin a sentence. I receive an error that the string index is out of range for the if statement.</p>
  
  <p>How can I fix my code to solve this issue?</p>