avoid 'use use'

Author: coke

doc/Language/faq.pod6

@@ -42,7 +42,7 @@ The vast majority of 6.d features are already implemented and available in
 in the Rakudo compiler without requiring any special pragmas, as they did
 not conflict with the 6.c specification.
 A smaller set of features and behaviours is available automatically if you
-use C<use v6.d.PREVIEW> pragma at the top of the file. The rest of about
+have the C<use v6.d.PREVIEW> pragma at the top of the file. The rest of about
 3100 new commits to the language specificication simply clarify previously
 undefined behaviour.