English words from https://github.com/first20hours/google-10000-english/raw/master/google-10000-english-no-swears.txt.
Japanese words from https://gist.github.com/nakaly/c2c855766ce1661e11396b09760b9598 (n1-n5), furigana from https://github.com/Doublevil/JmdictFurigana (not provided here due to its size).
Spanish words from Qiutian Zhang from http://corpus.rae.es/frec/10000_formas.TXT.