%%%------------------------------------------------------------------------------------------------------------
\begin{tikzpicture}

\begin{scope}

\node [anchor=west,draw,thick,minimum width=4em,minimum height=1.7em,fill=blue!20] (encoder) at (0,0) {模块};
\node [anchor=south,minimum width=4em,minimum height=1.7em] (space) at ([yshift=0.3em]encoder.north) {\footnotesize{目标系统}};

\begin{pgfonlayer}{background}
\node [rectangle,draw,thick,fill=red!20] [fit = (encoder) (space)] (system) {};
\end{pgfonlayer}

\node [anchor=north] (data) at ([yshift=-1em]system.south) {\scriptsize{\textbf{目标任务有标注数据}}};
\draw [->,thick] (data.north) -- ([yshift=-0.1em]system.south);
\node [anchor=north] (label) at ([yshift=-0em]data.south) {\scriptsize{(a) standard method}};

\end{scope}

\begin{scope}[xshift=2.8in]

\node [anchor=west,draw,dashed,thick,minimum width=4em,minimum height=1.7em,fill=blue!20] (encoder) at (0,0) {模块};
\node [anchor=south,minimum width=4em,minimum height=1.7em] (space) at ([yshift=0.3em]encoder.north) {\footnotesize{目标系统}};
\node [anchor=center,draw,thick,minimum width=4em,minimum height=1.7em,fill=green!20] (encoderpre) at ([xshift=-7em]encoder.center) {\footnotesize{语言模型}};
\draw [->,thick] (encoderpre.east) -- (encoder.west);

\begin{pgfonlayer}{background}
\node [rectangle,draw,thick,fill=red!20] [fit = (encoder) (space)] (system) {};
\end{pgfonlayer}

\node [anchor=north] (data) at ([yshift=-1em]system.south) {\scriptsize{\textbf{目标任务有标注数据}}};
\draw [->,thick] (data.north) -- ([yshift=-0.1em]system.south);
\node [anchor=north] (data2) at ([yshift=-1em,xshift=-7em]system.south) {\scriptsize{\textbf{大规模无标注数据}}};
\draw [->,thick] (data2.north) -- ([yshift=-0.1em]encoderpre.south);
\node [anchor=north] (label) at ([yshift=-0em,xshift=-4em]data.south) {\scriptsize{(b) pre-training + fine-tuning}};

\end{scope}

\end{tikzpicture}
%%%------------------------------------------------------------------------------------------------------------