I have the following Mathematica code:
ParametricPlot3D[{{0 + 0*t, 10 - 1*t, 9 - 1*t}, {7 - t, 7 - t,
6 - t}, {0, 0, -1}}, {t, 12, -20}]
The last "parametric curve" $(0, 0, -1)$ is a point I want to plot as a visible ball or disc or whatever. At the moment I can't see it.
How can I plot visible points in addition to parametric curves? I don't actually think I can state the 3D point and expect it to appear as I currently have it...
Currently the code displays the following:

UPDATE
A temporary fix for now is the following code:
ParametricPlot3D[{{0 + 0*t, 10 - 1*t, 9 - 1*t}, {7 - t, 7 - t,
6 - t}, {0 + Sin[t], 0 + Cos[t], -1}}, {t, 12, -20}]
It would be nice to plot a ball though...

