"Love is a hot and passionate, dear teacher, I want to give you a song..." This is when I sing the song, today I want to sing to my dear teacher!

“爱心一颗，热情似火，亲爱的老师，我要为你献上一支歌……”这是儿时我唱的歌，今天我要唱给我亲爱的老师！

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If you can search for the lyric properly, a solid result shows you that the TuneWiki app can give the lyrics to any song, and the Shazam app recognizes songs based on lyrics or sound clips.

FORBES: The Functional Web: Navigating The World Of Apps