Hi, guys!
Go to the links below to do some practise on possibility and certainty. Good luck!
http://www.autoenglish.org/gr.may3.i.htm
https://www.perfect-english-grammar.com/modal-verbs-of-probability-exercise-2.html
http://speakspeak.com/english-grammar-exercises/intermediate/intermediate-grammar-exercise-modal-verbs-for-present-probability-must-cant-could-may-might
https://elt.oup.com/student/englishfile/intermediate/a_grammar/file03/nef_int_grammar03_b02?cc=global&selLanguage=en
https://elt.oup.com/student/englishfile/intermediate/a_grammar/file03/nef_int_grammar03_b01?cc=global&selLanguage=en
