Fix typo spotted by Richie Hindle
diff --git a/Doc/lib/libpdb.tex b/Doc/lib/libpdb.tex
index bf779fe..fb2c1b9 100644
--- a/Doc/lib/libpdb.tex
+++ b/Doc/lib/libpdb.tex
@@ -262,7 +262,7 @@
again, or jump forward to skip code that you don't want to run.
It should be noted that not all jumps are allowed -- for instance it
-it not possible to jump into the middle of a for loop or out of a
+is not possible to jump into the middle of a for loop or out of a
finally clause.
\item[l(ist) \optional{\var{first\optional{, last}}}]