Orthographic projection practice with real parts: sloped faces, steps, slots and hidden lines. Rotate the part in 3D and look through it to see the edges behind. In “Pick the view”, find the correct front, top or side view among four drawings, with an explanation of every mistake; in “Draw the view”, draw it on a grid at the exact size, with visible or hidden lines, and it is checked automatically. Thirty parts in three levels, in first-angle projection (the European system), with PNG export to hand in your work.