Fix grammar error spotted by Sian Mountbatten

diff --git a/lib/doc/Intro.lyx b/lib/doc/Intro.lyx
index 93fb60f916d208d9728b0efe1cf18c4b474b2154..1a66dc444b080e2de8544348d39118aad1348f25 100644 (file)
--- a/lib/doc/Intro.lyx
+++ b/lib/doc/Intro.lyx
@@ -870,7 +870,7 @@ Navigate
 \begin_layout Standard
 In the printed manuals, all cross-references appear as the actual numbers
  for a chapter, section, subsection, and so on.
- In the LyX-file, however, all cross-references appear as a light-grey boxes
+ In the LyX-file, however, all cross-references appear as light-grey boxes
  like the following: 
 \begin_inset Graphics
        filename clipart/referenceQt4.png