Definition of "became"
became
/bɪˈkeɪm/
verb
(colloquial, nonstandard) past participle of become
Quotations
[…] and had the outlawry been confirmed, he muſt not only have remained ſo, but all his eſtate and effects (if any there were) would have became forfeited to the crown.
1768, William Murray, A ſhort examination into the conduct of Lord M--f--d through the affair of Mr. Wilkes, Staples Steare, page 13
Suppose you are given the semifactual assertion, "even if Nora had liked mathematics then she would have became a scientist" and then you find out that Nora did in fact become a scientist.
2007 January 26, Ruth M. J. Byrne, The Rational Imagination: How People Create Alternatives to Reality, MIT Press, page 140