A few minor improvements
diff --git a/Doc/ext/newtypes.tex b/Doc/ext/newtypes.tex
index df78d54..2b915f3 100644
--- a/Doc/ext/newtypes.tex
+++ b/Doc/ext/newtypes.tex
@@ -723,8 +723,9 @@
 \end{verbatim}
 
 For each subobject that can participate in cycles, we need to call the
-\cfunction{visit} function passed to the traversal method passing the
-subobject and the extra argument passed to the traversal method.
+\cfunction{visit} function, which is passed to the traversal method.
+The \cfunction{visit} function takes as arguments the subobject and
+the extra argument \var{arg} passed to the traversal method.
 
 We also need to provide a method for clearing any subobjects that can
 participate in cycles.  We implement the method and reimplement the
@@ -757,7 +758,7 @@
 \end{verbatim}
 
 That's pretty much it.  If we had written custom \member{tp_alloc} or
-\member{tp_free} slots, we'd need to modify then for cyclic-garbage
+\member{tp_free} slots, we'd need to modify them for cyclic-garbage
 collection. Most extensions will use the versions automatically
 provided.