PASSIVE VOIVE
http://www.agendaweb.org/verbs/passive-exercises.html
http://www.learnenglishfeelgood.com/esl-passive-voice-exercise2.html
PAST PERFECT SIMPLE AND PROGRESSIVE
http://www.englishpage.com/verbpage/verbs13.htm
http://speakspeak.com/english-grammar-exercises/upper-intermediate/past-perfect-simple-vs-past-perfect-continuous
http://www.englishtenses.com/test/romance_novel1
