old_contents: #!/usr/bin/env python
  import random
  Number_Of_Sentences_To_Generate = 20
  nouns = open('nouns.txt', 'r').read().splitlines()
  verbs = open('verbs.txt', 'r').read().splitlines()
  conjunctions = open('conjunctions.txt', 'r').read().splitlines()
  
  def clause(nouns, verbs):
      return [random.choice(nouns), " ", random.choice(verbs), " ", random.choice(nouns)]
  
  def generate_sentence(nouns, conjunctions, verbs):
      max_clauses = 3
      num_clauses = random.randrange(max_clauses) + 1
      sentence = []
      for i in range(num_clauses):
          sentence += clause(nouns, verbs)
          if i < (num_clauses - 1):
              sentence += [", ", random.choice(conjunctions), " "]
      return sentence
  
  for i in range(Number_Of_Sentences_To_Generate):
      print (''.join(generate_sentence(nouns, conjunctions, verbs)) + "\n").capitalize()
  
new_contents: #!/usr/bin/env python
  import random
  Number_Of_Sentences_To_Generate = 20
  nouns = open('nouns.txt', 'r').read().splitlines()
  verbs = open('verbs.txt', 'r').read().splitlines()
  conjunctions = open('conjunctions.txt', 'r').read().splitlines()
  
  def generate_sentence(nouns, conjunctions, verbs):
      max_clauses = 3
      num_clauses = random.randrange(max_clauses) + 1
      sentence = []
      for i in range(num_clauses):
          sentence += [random.choice(nouns), " ",
                       random.choice(verbs), " ",
                       random.choice(nouns)]
          if i < (num_clauses - 1):
              sentence += [", ", random.choice(conjunctions), " "]
      return sentence
  
  for i in range(Number_Of_Sentences_To_Generate):
      print (''.join(generate_sentence(nouns, conjunctions, verbs))
             + "\n").capitalize()
  
subject: remove tiny subroutine, better linebreaks