[Tex/LaTex] How to insert greek letters with subscript in text mode with latex

greekpackagessubscripts

I am trying to insert a greek letter with subscript in latex and I used textgreek package and it appears as h_a. I am making a poster using beamer but I wrote following sample code and it has the same problem.

\documentclass{article}
\usepackage{textgreek}
\begin{document}
 $\texteta \textsubscript{a}$
 \end{document}

Would you please help me? If the package textgreek is not good for mixing with subscript, please recommend other package that I can use.

Thank you!

Best Answer

\texteta etc. isn't meant for math mode, i.e. omit the $...$ characters -- that's why the symbols are called \text..., i.e. to be used in text mode

\documentclass{article}
\usepackage{textgreek}
\begin{document}

\huge
\begin{tabular}{ccc}
Text mode & & Math mode \tabularnewline
\texteta \textsubscript{a} &  & $\eta_{a}$
\end{tabular}
\end{document}

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