Vídeo com explicação: https://www.youtube.com/watch?v=SL3ciyAEcms

Link 1: https://www.english-4u.de/en/tenses-exercises/present-simple-progressive2.htm

Link 2: https://www.ego4u.com/en/cram-up/grammar/simpre-prepro/tests?test3

Link 3: http://www.hueber.de/shared/elka/Internet_Muster/Red2/3-19-002886-9_Muster.pdf