Typo

Chapters/Chapter02.tex

@@ -569,8 +569,8 @@ uninterpreted function, which uses model-driven Fourier-Motzkin
 elimination~\cite{Dan63} to learn new predicates from arithmetic
 conflicts and model-driven Ackermannization~\cite{MB08, Ack54} to
 learn new predicates from conflicts involving uninterpreted
-functions. This solver has shown to have performance comparable with
-existing state-of-the-art \dpllt solvers~\cite{JMB13}.
+functions. This solver has been shown to have performance comparable
+with existing state-of-the-art \dpllt solvers~\cite{JMB13}.
 
 %\subsection{Combination of theories}