snippet environment abbr env alias env options head \begin{${1}} ${2} \end{$1} snippet align options head \begin{align${1:#:options}} ${0} \end{align$1} snippet sum abbr sum options head \sum_{${0}}^{${1}} snippet satz abbr satz options head \begin{satz} ${0} \end{satz} snippet e options head \emph{${1}}${2} snippet b options head \textbf{${1}}${2} snippet proof abbr proof options head \begin{proof} ${0} \end{proof} snippet subsection abbr ss alias ss options head \subsection{${1}}${2} snippet subsubsection abbr sss alias sss options head \subsubsection{${1}}${2} snippet sum abbr sum options head \sum_{${0}}^{${1}}${2}