・I'll leave the decision to you. ＝I'll leave it to you to decide. 決定は君に任せる.

・I('ll) leave it [that] to you, sir. お任せいたします 《What's the fare [price]? のような質問に対する答え》.

・I leave that to your judgment. それは君の判断に任せる.

・The rest may be left to the reader's imagination. あとは読者の想像に任せよう.

・He leaves everything to chance. 彼は何をするにも運任せだ.

・I'll leave that entirely up to you. その事は全部君にお任せする.

・Just leave it [everything] to me! それは[万事]私に任せてくれ.