You're playing with fire!

（危ないわよ！）
　　ECC英会話podcasting にて紹介されていた表現。動物園にて、ライオンの檻の前でピザをちらつかせる男性を戒める女性の一言。

• play with fireで「危険なことをする」（take foolish risks.／to do something dangerous or risky.／to do something that could cause you great trouble later）。進行形で使われることが多いらしい。
• 日本語の「火遊び」というと、男女間での危険な関係を指すけれど、英語の場合はそれも含めてもっと広義に使える。ばかばかしいリスクを負うって感じ？
  • Be careful with that knife! You are playing with fire!
  • Don't you know you're playing with fire when you get involved with someone who's already married?
  • Dating the boss's daughter is playing with fire.
  • "Driving alone on isolated roads is playing with fire.
  • You are playing with fire if you get involved with that new project. You may lose much money.