Add or subtract. Simplify. \begin{array}{r}

\frac{2}{3} \\

+\frac{1}{3}

\end{array} \begin{array}{r}

\frac{4}{5} \\

+\frac{3}{5} \\

\hline

\end{array} \begin{array}{r}

\frac{5}{6} \\

+\frac{5}{6} \\

\hline

\end{array}