<SYSTEM_TASK:>
Solve the following problem using Python, implementing the functions described below, one line at a time
<END_TASK>
<USER_TASK:>
Description:
 def replace_suffixes_4(self, word):
 """ Perform replacements on even more common suffixes. """

        length = len(word)
        replacements = {'ational': 'ate', 'tional': 'tion', 'alize': 'al',
                        'icate': 'ic', 'iciti': 'ic', 'ical': 'ic',
                        'ful': '', 'ness': ''}

        for suffix in replacements.keys():
            if word.endswith(suffix):
                suffix_length = len(suffix)
                if self.r1 <= (length - suffix_length):
                    word = word[:-suffix_length] + replacements[suffix]

        if word.endswith('ative'):
            if self.r1 <= (length - 5) and self.r2 <= (length - 5):
                word = word[:-5]

        return word