“But. By many writers this word (in the sense of except) is regarded as a preposition, to be followed by the objective case: ‘All went but him.’ It is not a preposition and may take either the nominative or objective case, to agree with the subject of the object of a verb. ‘All went but he.’ ‘The natives killed all but him.'”
Excerpted from: Bierce, Ambrose. Write it Right: A Little Blacklist of Literary Faults. Mineola, NY: Dover, 2010.
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