DirectX 8.0a

I keep getting an automation error when I execute the following line in the Render() Function:

g_D3DDevice.DrawPrimitive D3DPT_TRIANGLELIST, 0, 1

where g_d3dDevice is a Direct3dDevice8. I am extremely new to DirectX Programming so I'm sure the answer is pretty easy. A little help would be nice!

Thanks

JC