Two lines $A B$ and $C D$ are cut by a transversal $E F$, as shown in the figure. Identify the given pair of angles as adjacent angles, vertically opposite angles, alternate angles, corresponding angles or co-interior angles. (i) $\angle 6$ and $\angle 7$ (ii) $\angle 3$ and $\angle 4$ (iii) $\angle 4$ and $\angle 8$ (iv) $\angle 1$ and $\angle 5$ (v) $\angle 3$ and $\angle 5$ (vi) $\angle 2$ and $\angle 4$ (vii) $\angle 4$ and $\angle 5$ (viii) $\angle 2$ and $\angle 7$ (ix) $\angle 3$ and $\angle 6$ (x) $\angle 4$ and $\angle 6$ (xi) $\angle 2$ and $\angle 6$ (xii) $\angle 1$ and $\angle 4$