visualizing lines and solids

How can I see a line passing through a solid? For example, a line passing in the middle of a cube.

OBS.: Sorry, I don´t know English very well.

I’m not sure exactly what you’re after, but if you draw the solid as a wireframe you’ll be able to see its edges in relation to the given line.

Alternatively, if you draw the line first then draw the cube slightly alpha-blended, you’ll be able to see a solid with a ghostly impression of the line passing through it.