https://www.grammar-monster.com/glossary/modal_verbs.htm

https://www.britishcouncil.org.mx/blog/modal-verbs

https://englishlive.ef.com/es-mx/blog/laboratorio-de-gramatica/modal-verbs/

https://www.abaenglish.com/es/verbos-modales-ingles/

https://www.berlitz.com/es-mx/blog/modal-verbs

https://www.superprof.es/apuntes/idiomas/ingles/gramatica-inglesa/modal-verbs/modal-verbs-2.html

https://agendaweb.org/verbs/modals-mixed-2-exercises.html

https://www.elt-els.com/2015/02/must-modal-verbs-multiple-choice-test.html

https://www.eslgamesplus.com/modal-verbs-can-could-might-must-should-would-catapult/

https://wordwall.net/es-es/community/modal-verbs-game

https://www.englishclub.com/esl-games/grammar/jumbled-modals.php

https://www.turtlediary.com/game/modal-verbs.html

https://wordwall.net/es-es/community/grammar-modal-verbs

https://www.baamboozle.com/tag/modal-verbs