\documentclass{article}
\usepackage{qtree}
\title{qtree -- pakietomat.wordpress.com}
\begin{document}
Przykłady użycia pakietu \textit{qtree}. Pełny opis na stronie paczkomat.wordpress.com (http://pakietomat.wordpress.com/2013/05/17/qtree/)
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\Tree [.A [ a b ] .B C ]
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\Tree [.A [ a b ] .B !\qsetw{4cm} C ]
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\Tree [.A [ a b ] .B !\qsetw{0.5cm} C ]
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\vspace{1cm}
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\Tree [.A [ a !\qsetw{6cm} b ] .B !\qsetw{1cm} C ]
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\Tree [.A [ a !\qsetw{6cm} b ] .B !\qsetw{9cm} C ]
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\vspace{1cm}
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\Tree [.X leaf_1 [.Y leaf_2 [.Z leaf_3 last ] ] ]
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\vspace{1cm}
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\Tree [.X leaf_1 [.Y leaf_2 [.Z leaf_3 last !{\qbalance} ] ] ]
\end{document}