diff --git a/dd.1 b/dd.1
index fd1a3af..31fe00e 100644
--- a/dd.1
+++ b/dd.1
@@ -21,7 +21,7 @@ the
 option.
 .Sh OPTIONS
 .Bl -tag -width Ds
-.It Ar bs Op Ar [=N]
+.It Ar bs Ns Op Ar =N
 If
 .Ar bs
 is not specified, the default blocksize is 64kB. If
@@ -59,5 +59,6 @@ Seek
 blocks from the beginning of the output before copying.
 .It Ar skip=N
 Skip
-.Ar N blocks from the beginning of the input before copying.
+.Ar N
+blocks from the beginning of the input before copying.
 .El