An electromotive soil cultivation appliance for cultivating soil in the fields of agriculture and horticulture is described, particularly a rotary hoe with an asynchronous rotary current motor for driving a rotatable cultivating tool. The printing method of the image forming system includes inputting image data to be printed; and, if adjacent first and second objects included in the input image data have different LPIs, emphasizing at least one of boundaries of the first and second objects and printing the image data with an emphasized boundary. The variable valve rotates about each pivot member provided thereon, thereby adjusting the flow velocity of fluid guided from the flow path to the turbine. The chuck arm 17 holds the chuck disk 11 rotatably.