Each execute buffer contains a vertex list followed by an instruction stream. The instruction stream defines how the vertex list should be rendered; it is based on indices into the vertex list.
Although you can choose to use transformed and lit vertices (D3DTLVERTEX), vertices that have only been lit (D3DLVERTEX), or vertices that have been neither transformed nor lit (D3DVERTEX), you can have only one of each type of vertex in a single Direct3DExecuteBuffer object. Some execute buffers are used only to change the state of one or more of the modules in the graphics pipeline; these execute buffers do not have vertices.
For more information about the handling of vertices in execute buffers, see Vertex Formats.