\documentclass{article}
\usepackage[T1]{fontenc}
\usepackage[light]{merriweather}
\usepackage{microtype}
\usepackage{lipsum}
\begin{document}

\section{Merriweather}
\subsection*{Regular}
\lipsum[1]

\subsection*{Italic}
\textit{\lipsum[2]}


\subsection*{Bold}
\textbf{\lipsum[3]}

\subsection*{Bold Italic}

\textbf{\textit{\lipsum[4]}}

\subsection*{Small Capitals}

\textsc{\lipsum[9]}

\subsection*{Light}

{\merriweatherlight\lipsum[5]}


\subsection*{Light Italic}

\textit{\merriweatherlight\lipsum[6]}

\subsection*{Black}

{\merriweatherblack\lipsum[7]}


\subsection*{Black Italic}

\textit{\merriweatherblack\lipsum[8]}


\subsection*{Numbers}

1234567890

\section{Merriweather Sans}\sf

\subsection*{Regular}
\lipsum[1]

\subsection*{Italic}
\textit{\lipsum[2]}

\subsection*{Bold}
\textbf{\lipsum[3]}

\subsection*{Bold Italic}

\textbf{\textit{\lipsum[4]}}

\subsection*{Small Capitals}

\textsc{\lipsum[9]}

\subsection*{Light}

{\merriweathersanslight\lipsum[5]}

\subsection*{Light Italic}

\textit{\merriweathersanslight\lipsum[6]}

\subsection*{Black}

{\merriweathersansblack\lipsum[7]}

\subsection*{Black Italic}

\textit{\merriweathersansblack\lipsum[8]}

\subsection*{Numbers}

1234567890

\end{document}