http://www.englishexercises.org/makeagame/viewgame.asp?id=1791
http://www.agendaweb.org/grammar/conjunctions-exercises.html
http://www.agendaweb.org/grammar/conjunctions-connectors-exercises.html
http://www.tolearnenglish.com/cgi2/myexam/liaison.php?liaison=_connecteur_