preterite-present

But, to mix socio-linguistics with grammar, the verb “may” is a preterite-present verb, which means that it was originally a strong verb (the inner vowel changed to indicate tense, like “swim, swam, swum”) but the preterite (“past”) took on a present meaning. (due to the social climate, the speakers had to improvise due to their two-tense system.)

The “may” and “might” follow-up « Motivated Grammar 2009

61 Paradoxically enough, the very purists who performed the purging showed a preference for got (though not forgot), and it survives in correct English today in the preterite-present form, as in “I have got, ” whereas in American, both vulgar and polite, the elder and more regular gotten is often used.

Chapter 9. The Common Speech. 3. The Verb Henry Louis 1921