def tag_clause_annotations(self):
        """Tag clause annotations in ``words`` layer.
        Depends on morphological analysis.
        """
        if not self.is_tagged(ANALYSIS):
            self.tag_analysis()
        if self.__clause_segmenter is None:
            self.__clause_segmenter = load_default_clausesegmenter()
        return self.__clause_segmenter.tag(self)