Forth grande, this the homework that you will show tour teacher next Thursday, Dec-10,2015. Remember, it is for you tí práctica and eran points.

Use this link to better understand.
http://www.perfect-english-grammar.com/modal-verbs.html

This the exercise you need to do.
Go forma it!
http://www.myenglishpages.com/site_php_files/grammar-exercise-modals.php
Somebody said, learning by doing.