def pad_word_chars(words):
    """
    Pad the characters of the words in a sentence.
    Input:
        - list of lists of ints (list of words, a word being a list of char indexes)
    Output:
        - padded list of lists of ints
        - padded list of lists of ints (where chars are reversed)
        - list of ints corresponding to the index of the last character of each word
    """
    max_length = max([len(word) for word in words])
    char_for = []
    char_rev = []
    char_pos = []
    for word in words:
        padding = [0] * (max_length - len(word))
        char_for.append(word + padding)
        char_rev.append(word[::-1] + padding)
        char_pos.append(len(word) - 1)
    return char_for, char_rev, char_pos