diff --git a/Secciones/background.tex b/Secciones/background.tex
index 7e7a9a0..93402ae 100644
--- a/Secciones/background.tex
+++ b/Secciones/background.tex
@@ -6,14 +6,15 @@
 \label{cha:background}
 
 \section{Program slicing}
-\textsl{Program slicing} \cite{Wei81,Sil12}\sergio{hay alguna razon para que \cite{Sil12} no este en la intro?, la unica cita alli es\cite{Wei81}. Propongo eliminar \cite{Sil12} por homogeneidad} is a debugging technique that
-answers the question: ``which parts of a program affect a given statement and
+\textsl{Program slicing} \cite{Wei81,Sil12}\sergio{hay alguna razon para que \cite{Sil12} no este en la intro?, la unica cita alli es\cite{Wei81}. Propongo eliminar \cite{Sil12} por homogeneidad}\josep{mas bien, tendria que estar 13 tambi\'en en la intro} is a debugging technique that
+answers the question: ``which parts of a program \josep{do?}
+affect a given statement and
 set of variables?'' The statement and the variables are the basic input to create a slice
 and are called the \textsl{slicing criterion}. The criterion can be more
 complex, as different slicing techniques may require additional pieces of input.
 The \textsl{slice} of a program is the list of statements from the original
 program ---which constitutes a valid program--- whose execution will result in
-the same values for the variables (selected in the slicing criterion). 
+the same values for the variables \josep{frase enrrevesada. yo la. cambiaria. De todas formas, para que sea correcta le sobran los parentesis }(selected in the slicing criterion). 
 There exist two fundamental dimensions along which the problem of slicing can be
 proposed \cite{Sil12}:
 
@@ -22,13 +23,13 @@ proposed \cite{Sil12}:
 \begin{itemize}
 	\item \textsl{Static} or \textsl{dynamic}: slicing can be performed
 		statically or dynamically.
-		\textsl{Static slicing} \cite{Wei81} produces slices which consider all
+		\textsl{Static slicing} \cite{Wei81} produces slices which\josep{that} consider all
 		possible executions of the program: the slice will be correct regardless of the input supplied.
 		In contrast, \textsl{dynamic slicing} \cite{KorL88} considers a single execution of the program, thus, limiting the slice to
 		the statements present in an execution log. The slicing criterion is
-		expanded to include a position in the log that corresponds to one
+		expanded to include a position in the log\josep{execution history} that corresponds to one
 		instance of the selected statement, making it much more specific. It may
-		help find a bug related to indeterministic behavior (such as a random
+		help \josep{to}find a bug related to indeterministic behavior (such as a random
 		or pseudo-random number generator), but \sergio{, despite selecting the same slicing criterion, the slice }must be recomputed for each case\sergio{different input value/execution considered?}
 		being analyzed.
 	\item \textsl{Backward} or \textsl{forward}: \textsl{backward slicing}
diff --git a/Secciones/motivation.tex b/Secciones/motivation.tex
index a673802..dac2f1e 100644
--- a/Secciones/motivation.tex
+++ b/Secciones/motivation.tex
@@ -9,7 +9,7 @@
 
 Program slicing~\cite{Wei81} is a debugging technique that, given a line of
 code and a set of variables of a program, simplifies such program so that the only parts
-left of it are those that affect or are affected by the values of the selected variables.
+left of it are those that affect or are affected by the values of the selected variables. \josep{aqui, antes del ejemplo, habria que decir de manera informal que es un slice y que es un SC}
 
 \sergio{Se me hace corta esta definicion y me faltan algunas utilidades del program slicing, por que se usa? Realmente no se usa solo en depuracion. Tiene mas usos, esto ademas da referencias a poner si queremos.}