\begin{tikzpicture}
  \node (ged) at (0,1) {$ged$};
  \node (highschool) at (0,0) {$highschool$};
  \node (bachelors) at (2,0) {$bachelors$};
  \node (phd) at (4,0) {$phd$};
  \draw [->] (ged) -- (bachelors);
  \draw [->] (highschool) -- (bachelors);
  \draw [->] (bachelors) -- (phd);
\end{tikzpicture}

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%%% TeX-master: "../../morphology"
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