Explicação através de um vídeo: https://www.youtube.com/watch?v=0HPKwhngB-U
Link 1: http://www.english-grammar.at/worksheets/adjective_adverb/ad5.pdf
Link 2: http://www.english-grammar.at/worksheets/adjective_adverb/ad6.pdf
Link 3: http://www.english-grammar.at/worksheets/adjective_adverb/ad7.pdf
