It is a collection of Japanese language problems that you can enjoy for free. This is the definitive edition of the Japanese language learning app with an overwhelming volume of 4500 questions in total, including 3800 single-question, single-answer questions and 700 four-choice questions.

question and answer question
"Facts, proverbs, idioms", "Four-letter idioms", "Kanji (readings and idioms)", "Kanji (readings and kana)", "Kanji (readings and four-letter idioms)", "Kanji (readings and place names)", "Kanji" (reading/foreign words), Kanji (reading/general), Kanji (radicals), Kanji (writing), Kanji (others), Antonyms, Honorifics/Humble words/Polite words, Old words ( (meaning)”, “Ancient language (Modern language→Ancient language)”, “Japanese literature”, “Foreign literature”, “Japanese trivia/others”