>>813-814
スマソ、なんか Trueにならなくね?

>>> word1 = 'abc'
>>> word2 = 'def'
>>> word3 = 'ghi'
>>> sstr = 'aaabcddd'
>>> s = set(sstr.split())
>>> {word1, word2, word3} & s != set()
False
>>> s = set('zzzzzzz'.split())
>>> {word1, word2, word3} & s != set()
False
>>>