\documentclass{article}
\begin{document}
\begin{table}
\centering
\caption{Context Free Grammar for Sum of Multiplicative/Exponential Terms}
\label{tab:rscfg}       % Give a unique label
\begin{tabular}{lll|lll|lll}  
Exp & $\rightarrow$ & Trm & Trm & $\rightarrow$ & Trm Mul Trm & Add $\rightarrow$ & "+" \textbar "-" \\
Exp & $\rightarrow$ & Trm Add Trm  &Trm & $\rightarrow$ & Var   & Mul $\rightarrow$ & "*" \textbar "/" \\
& &  & Trm & $\rightarrow$ & Const   & Var $\rightarrow$ & "T" \textbar "V"\\
\end{tabular}
\end{table}
\end{document}