http://grammar.ccc.commnet.edu/grammar/cgi-shl/quiz.pl/modal_quiz.htm

Modal Auxiliaries for deduction and propability

http://www.englishexercises.org/makeagame/viewgame.asp?id=5901

http://www.autoenglish.org/gr.may3.pdf

http://www.eltbase.com/get_quiz.php?id=59

http://elt.oup.com/student/naturalenglish/int/a_grammar/unit11/neint_grammar11_exp;jsessionid=BBE7E85472842E2D4A7E487B065B3650?cc=cl&selLanguage=en

Modal for  Prohibition

http://www.englishclub.com/grammar/verbs-modals-have-to-must-not-3.htm

http://www.learnenglish-online.com/grammar/modals/obligation.html