# -*- coding: utf-8 -*-

class ParserError(Exception):
  pass

class Sentence:
  def __init__(self, subject, verb, obj):
    self.subject = subject[1]
    self.verb = verb[1]
    self.object = obj[1]

  def peek(word_list):
    if word_list:
      word = word_list[0]
      return word[0]
    else:
      return None
