There are simply too many pairs in there that simply aren't antonyms ...
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Antonyms is a new educational English game in which you can test your knowledge of English words and their opposite meanings!
Go for highscores and compare your score with people from all around the world!
Three game modes included.
*** Free mobile versions ***
Google Play: https://play.google.com/store/apps/details?id=air.com.littlebigplay.games.antonyms
iOS: https://itunes.apple.com/us/app/antonyms-game/id1312775942?ls=1&mt=8
Amazon: https://www.amazon.com/gp/mas/dl/android?p=air.com.littlebigplay.games.antonyms
Sugar and salt are not antonyms, neither are sweet and salty