diff --git a/chapter06/gcc.xml b/chapter06/gcc.xml
index b2b0cd6b2..bcdf73571 100644
--- a/chapter06/gcc.xml
+++ b/chapter06/gcc.xml
@@ -127,7 +127,7 @@ cd ../gcc-build</userinput></screen>
     <para>A few unexpected failures cannot always be avoided. The GCC developers
     are usually aware of these issues, but have not resolved them yet. In
     particular, the <filename class="libraryfile">libmudflap</filename> tests
-    are known be particularly problematic as a result of a bug in GCC
+    are known to be particularly problematic as a result of a bug in GCC
     (<ulink url="http://gcc.gnu.org/bugzilla/show_bug.cgi?id=20003"/>).
     Unless the test results are vastly different from those at the above URL,
     it is safe to continue.</para>