course: Foundations of Higher Math

Let $\displaystyle A=\left\{1,2,3,4\right\}$. Give an example of a relation on A that is reflexive and transitive, but not symmetric.

My question is, does my relation have to include all of the pairs $\displaystyle \left\{(1,1),(2,2),(3,3),(4,4)\right\}$ to be reflexive?

For example, say my relation is $\displaystyle R=\left\{(1,1),(3,3),(1,3)\right\}$.