\documentclass{article}
\usepackage[T1]{fontenc}
\begin{document}

\begin{tabular}{|c|c|c|c|c|}	

\hline
 	&	\multicolumn{2}{|c|}{Singular}	&	\multicolumn{2}{|c|}{Plural}	\\	
\hline
 	&	English	&	\textbf{Gaeilge}	&	\textbf{English}	&	\textbf{Gaeilge}	\\	
\hline
1st Person	&	at me	&	\textbf{agam}	&	at us	&	\textbf{againn}	\\	
\hline
2nd Person	&	at you	&	\textbf{agat}	&	at you	&	\textbf{agaibh}	\\	
\hline
3rd Person	&	at him	&	\textbf{aige}	&	at them	&	\textbf{acu}	\\	
\hline
 	&	at her	&	\textbf{aici}	&	 	&	 	\\	
\hline
\end{tabular}

\end{document}

.
