alligned1 = 'I am going to go to some show'
alligned2 = 'I am not going to go the show'
results = []
word_pairs = zip(alligned1.split(), alligned2.split())
for k, v in itertools.groupby(word_pairs, key=lambda pair: pair[0] == pair[1]):
    if k:
        words = [pair[0] for pair in v]
results.append(' '.join(words))
print(results)
Сопоставление Python слов с одинаковым индексом в строке