Do you need to keep on practising a bit more? Here you will find very nice activities!!Game 1
http://learnenglishkids.britishcouncil.org/en/grammar-games/comparatives-and-superlatives
Game 2
http://www.marks-english-school.com/games/basketball.html
Game 3
http://www.eslkidsworld.com/Interactive%20games/Grammar%20Games/Comparative%20&%20Superlatives/comparatives%20and%20superlatives%20animals%20football%20quiz.html
Exercise 1
http://www.softschools.com/quizzes/grammar/adjectives/quiz328.html
Exercise 2
http://www.learnenglish-online.com/grammar/tests/superlativecomparative.html
