Kenneth G. Wilson (1923?). The Columbia Guide to Standard American English. 1993.
may, might (auxs.)
For events in the present or immediate future, use either may or might (I may [might] decide to go after all), but for past time, most Standard users still prefer only might, as in Yesterday I might have decided to stay home, not the increasingly encountered Yesterday I may have decided to stay home. Journalese is now peppered with may where until recently might has been solidly entrenched. See also CAN (1); COULD; SEQUENCE OF TENSES.
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