I want to identify specific words in a sentence and draw an arrow from one to the other

I’m trying to use tikz to draw a curved arrow from "he" to "John". I’m almost certain that the problem is using a node within a node, but I can’t think of another way to do this.

begin{tikzpicture}

node at (10,5) {node(top){John} thinks that node(bottom){he} is a genius.]]]] – coreference};

draw[->] (bottom)..(5,4)..(top);

end{tikzpicture}

For reference, here is the entire code with irrelevant parts removed.

documentclass[addpoints]{exam}
usepackage[utf8]{inputenc}
usepackage{kotex}
usepackage{tikz-qtree-compat} %This seems to be necessary with covington
usepackage{tikz} 
usepackage{tikz-qtree}
usepackage{covington}



begin{document}
%This code creates the text before the first question
%-------------------------------------------------------------------
begin{center}
fbox{fbox{parbox{5.5in}{centering
textbf{통사론 종합시헙 (박사)} - closed book
Please answer textbf{textit{three}} of the following four questions.
받안지를 양면으로 쓰십시오}}}
end{center}

vspace{5mm}

makebox[textwidth]{성명 (글):enspacehrulefill}

vspace{5mm}

makebox[textwidth]{성명 (영어):enspacehrulefill}
%-------------------------------------------------------------------

%Here, the questions begin
begin{questions}


question Two possible models for wh-movement are the following.

begin{tikzpicture}

node at (10,5) {[textsubscript{CP} node(top){wh-XPtextsubscript{textit{i}}} … [CP … [CP … [VP node(bottom){textit{ttextsubscript{i}}}]]]] – direct movement};

draw[->] (bottom)..(5,4)..(top);

end{tikzpicture}



end{questions}


end{document}