Example 1. A die is rolled. Let's denote the events: $A$ - "rolling a six", $B$ - "rolling a three", $C$ - "rolling an even number", $D$ - "rolling a number that is a multiple of three". What are the relationships between these events?
Solution. If six points fall, then an even number of points also falls, i.e., event $A$ implies event $C: A \subset C$. Reasoning similarly, we get $A \subset D, B \subset D, A+B=D, C \cdot D=A$.