普通にキーボードで入力 ↓矢印で変換 ↑↓矢印で変換結果を選択 →矢印で決定 ←矢印で削除
For non-japanese-speakers In order to type thousands of varieties of kanji characters on pc with a normal keyboard, we Japanese typically use a software called IME, which converts alphabet letters representing the pronouciation of kanji into Japanese sentences. And it is, what I recreated on scratch. To type "こんにちは世界" ("Hello World" in Japanese), press "konnnitihasekai", press ↓ key to convert, and → to accept the result.
