When you put sugar inside of a cup with water, the sugar is still visible because it's molecules have just gotten in touch with water molecules. The sugar molecules are still attracted to each other but as you stir it, it seems to disappear but not completely. When the water is stirred sugar mix with water and water molecules place themselves between the sugar ones.
Conclusion: It suggests that the sugar molecules are more attracted to water molecules which is why they easily separate from each other.