@staticmethod
def _abbreviate(phrase: str) ->str:
    """return words replaced with abbreviations"""
    subs = [('Hash Join', 'HJ'), ('Merge Join', 'MJ'), ('Product Join',
        'PJ'), (' Join', '-J'), ('Product', 'Prod'), ('Inclusion ', '+'), (
        'Exclusion ', '-'), ('Dynamic ', 'D-'), ('Correlated', 'Corr')]
    for word, abbr in subs:
        if word in phrase:
            phrase = phrase.replace(word, abbr)
    return phrase
