How the word "ひみつ（秘密）" is translated into English
これはみんなには秘密です。
秘密を教えてくれる？
友だちの秘密は話しません。
"ひみつ（秘密）" is in the lesson "Stories" (Level 33), along with 14 other useful words. LinDuo has 180 topic lessons like this one, 2,379 words in total. Every word has an illustration, a transcription and pronunciation in a female and a male voice. Just 10–15 minutes a day is enough to learn them all. Free, and works offline.
