With every action, there is an opposite and equal reaction. This applies to shadows as well. If you place a shadow underneath an object, some of this shadow should be reflected back onto the object, thus anchoring the object to Shadows the shadow and the surface on which it sits. Without this anchoring effect, objects will appear as if they are hovering (an effect you wouldn't want unless you were trying to make an object appear as though it were floating, as in Figure 2-41.
To create this anchoring shadow, add subtle amount of shadow to the object itself on multiplied layer, particularly where the object gets closer to the ground or another object. As an object gets closer to the ground or another object, the shadow will become progressively darker . After the application of the anchoring shadow, the object appears properly grounded. Note the anchoring shadow around the underside of the oranges in Figure 2-42.