You can add a card to the deck by clicking the Add button for the deck or in the Deck Browser if a deck is selected.
Note that depending on the deck type, these fields are required.
Kana Vocabulary: Kana Word (Hiragana/Katakana only), English Meaning (Alphanumeric)
Vocabulary: Japanese Word (Kanji and Kana), English Meaning (Alphanumeric), Kana (the reading of the word, Hiragana only)
Kanji: Kanji, English, Primary Reading (Kana only), Primary Reading (Onyomi/Kunyomi)
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