title: How to add underscores and remove them when the user inputs the correct letter?
body: <p>I'm having difficulty in adding underscores in my program. Also what is troubling me is that I can't seem to figure out how to remove the underscores when the user inputs the correct letter.</p>
  
  <pre class="lang-rb prettyprint-override"><code>class Game
  
  attr_reader :guess_count, :is_over, :word_length
  
  def initialize (secret_word)
      @secret_word = secret_word
      @guess_count = 0 
      @is_over = false 
      @word_length = secret_word.length
  end 
  
  def check_word(guess)
      @guess_count += 1
      if @secret_word == guess 
          puts "Congratulations!"
          @is_over = true 
      else 
          @is_over = false
          puts "Sorry, try again!"
      end 
  end 
  
  def subtract_guess_count
      counter = @word_length - @guess_count
  end 
  
  end
  
  puts "User 1, What is your secret word?"
  secret_word = gets.chomp
  
  anything = Game.new(secret_word)
  
  while !anything.is_over
      puts "User 2, Guess the secret word"
          guess = gets.chomp
      anything.check_word(guess)
          if anything.subtract_guess_count == 0
              puts "You lose! the correct word was #{secret_word}"
              exit!
          end 
          if anything.is_over == false
              puts "You have #{anything.subtract_guess_count} left!"
          end 
  end 
  </code></pre>