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Leave the sleeping dog alone.
Literal
Sleeping dog [topic-は] that-state [as-it-is-ままに] leave-alone-[imperative-おけ].
そのまま ('as it is, as-is') + にしておく ('leave it in that state') is a set phrase for 'leave alone.' Plain imperative おけ. Another rendering of 'let sleeping dogs lie,' this one without the causative.