When drawing three views of geometric figures, the line of sight must be perpendicular to the plane where the geometric figures are placed, and stand above the figures when looking at the top view;

The front view and left view of the same object are drawn in the same way, that is, the height and width of the object are determined first, and then the front view and left view are drawn. The top view can be drawn from above according to the length and width of the object.