git-show-ref.txt: remove word and make consistent

Under is better than in because of the nested nature of the .git
directory.

"also using" sounds a little odd, plus we say combined with later on so
just use that.

Signed-off-by: Stephen Boyd <bebarino@gmail.com>
Signed-off-by: Junio C Hamano <gitster@pobox.com>
diff --git a/Documentation/git-show-ref.txt b/Documentation/git-show-ref.txt
index 2f173ff..98e294a 100644
--- a/Documentation/git-show-ref.txt
+++ b/Documentation/git-show-ref.txt
@@ -24,7 +24,7 @@
 refs from stdin that don't exist in the local repository.
 
 Use of this utility is encouraged in favor of directly accessing files under
-in the `.git` directory.
+the `.git` directory.
 
 OPTIONS
 -------
@@ -50,7 +50,7 @@
 -s::
 --hash::
 
-	Only show the SHA1 hash, not the reference name. When also using
+	Only show the SHA1 hash, not the reference name. When combined with
 	--dereference the dereferenced tag will still be shown after the SHA1.
 
 --verify::