Change wording as Eli Bendersky suggests.

Doc/howto/argparse.rst

@@ -668,8 +668,8 @@ Conflicting options
 So far, we have been working with two methods of an
 :class:`argparse.ArgumentParser` instance. Let's introduce a third one,
 :meth:`add_mutually_exclusive_group`. It allows for us to specify options that
-conflict with each other. Let's also change the rest of the program to make the
-new functionality makes more sense:
+conflict with each other. Let's also change the rest of the program so that
+the new functionality makes more sense:
 we'll introduce the ``--quiet`` option,
 which will be the opposite of the ``--verbose`` one::