To push or cause s.t. to fall over [N-, ka-]; to lay s.t. down [ma-].
The -un imp. focuses on s.t. being pushed or tipped over. The -an imp. focuses on the thing that s.t. is pushed over on to. The pa--un imp. focuses on the thing that is laid down.
Who pushed a banana tree over on my corn?
Who caused my banana tree to fall over?