MODAL VERBS IN THE PAST

Here is some practice on modals in the past:

https://www.english-at-home.com/lessons/grammar-exercise-past-modals/
https://www.esl-lounge.com/student/grammar/4g66-past-modals-exercise.php
https://www.perfect-english-grammar.com/could-have-should-have-would-have-exercise-1.html
https://www.test-english.com/grammar-points/b1-b2/past-modal-verbs/
https://www.test-english.com/grammar-points/b1-b2/past-modal-verbs/2/
https://www.test-english.com/grammar-points/b1-b2/past-modal-verbs/3/
http://www.autoenglish.org/modalverbs/gr.might.i.htm