http://home.nordnet.fr/~rmaufroid/pupitre/pastpresentfuture/pastpresentfuturelien.html
http://www.learnenglish.org.uk/grammar/archive/grammar_games_index_page01.html
Past simple
http://www.historyonthenet.com/Lessons/anachronism/anachronismspot.htm
http://www.michellehenry.fr/preterit.htm#ps
