doc: improve ls --help grammar

* src/ls.c (usage): Improve grammar.
Reported by Peng Yu.

1 files changed, 1 insertions, 1 deletions

diff --git a/src/ls.c b/src/ls.c
index a16725462..c604e14da 100644
--- a/src/ls.c
+++ b/src/ls.c
@@ -4588,7 +4588,7 @@ usage (int status)
       printf (_("Usage: %s [OPTION]... [FILE]...\n"), program_name);
       fputs (_("\
 List information about the FILEs (the current directory by default).\n\
-Sort entries alphabetically if none of -cftuvSUX nor --sort.\n\
+Sort entries alphabetically if none of -cftuvSUX nor --sort is specified.\n\
 \n\
 "), stdout);
       fputs (_("\