Write down the two pairs of vertically opposite angles.

From the diagram:
The left angle ($u$) is vertically opposite the right angle ($p$).
The upper angle ($f$) is vertically opposite the lower angle ($m$).

$$\angle u \textrm{ and } \angle p$$ $$\angle f \textrm{ and } \angle m$$

The two pairs of vertically opposite angles are $(\angle u, \angle p)$ and $(\angle f, \angle m)$.

(\angle u,\ \angle p)\ and\ (\angle f,\ \angle m)