def build_add_prompt(offer_p, offer_f, offer_N):
    """Build a prompt for adding a word to a dictionary.

    :param offer_p: offer a (p)rogramming language dictionary
    :type offer_p: bool
    :param offer_f: offer a (f)ile-specific dictionary
    :type offer_f: bool
    :param offer_N: offer to create a (N)ew file-specific dictionary
    :type offer_p: bool
    :returns: prompt string

    """

    prompt = """\
      Subtoken '%s':
         (b)ack, (i)gnore, add to (n)atural language dictionary"""
    if offer_p:
        prompt += """, add to
         (p)rogramming language dictionary"""
    if offer_f:
        prompt += """, add to
         (f)ile-specific dictionary"""
    if offer_N:
        prompt += """, add to
         (N)ew file-specific dictionary"""
    prompt += """ [i]"""
    return prompt