3D vs 2D drawing

When you are drawing, it is best to use three dimensions, because it gives the picture a lifelike feeling. If it is two dimensional, it makes it seem boring, and dead. That is precicely the opposite of what you want, right? How do you get this effect, some may ask? Well, the best thing you can do is learn to shade. Shading gives the effect of depth, and space. When you learn to efficiently shade, your drawings will look more life-like. So, good luck!