http://www.alphaingles.com/2011/03/primer-y-segundo-condicional-como-y.html
http://www.youtube.com/watch?v=0uJu4rHCM58

http://www.curso-ingles.com/gramatica-inglesa/pasado.php
http://www.youtube.com/watch?v=_mDjicwL4Ss

http://www.aprende-gratis.com/ingles/curso.php?lec=presente-simple
http://www.youtube.com/watch?v=8Q3jVyLaVdE