diff --git a/collects/scribblings/guide/scripts.scrbl b/collects/scribblings/guide/scripts.scrbl
index cfea9dd0f8..5647b65e65 100644
--- a/collects/scribblings/guide/scripts.scrbl
+++ b/collects/scribblings/guide/scripts.scrbl
@@ -5,9 +5,9 @@
 
 @title[#:tag "scripts"]{Scripts}
 
-Scheme files can be turned into executable scripts on Unix and Mac OS
-X.  On Windows, one option is to use a compatibility layer like Cygwin,
-or write scripts as batch files.
+Scheme files can be turned into executable scripts under Unix and Mac
+OS X.  Under Windows, a compatibility layer like Cygwin support the
+same kind of scripts, or scripts can be implemented as batch files.
 
 @section{Unix Scripts}
 
@@ -119,7 +119,7 @@ the script file turns out to be valid input to both @exec{/bin/sh} and
 @section{Windows Batch Files}
 
 A similar trick can be used to write Scheme code in Windows
-@as-index{@tt{batch}} files:
+@as-index{@tt{.bat}} batch files:
 
 @verbatim[#:indent 2]|{
   ; @echo off
diff --git a/collects/scribblings/reference/numbers.scrbl b/collects/scribblings/reference/numbers.scrbl
index 631b168062..b10430ef4c 100644
--- a/collects/scribblings/reference/numbers.scrbl
+++ b/collects/scribblings/reference/numbers.scrbl
@@ -589,9 +589,9 @@ produces @scheme[+nan.0] in the case that neither @scheme[y] nor
 Returns @scheme[#t] when the @scheme[m]th bit of @scheme[n] is set in @scheme[n]'s
         (semi-infinite) two's complement representation.
                    
-This is equivalent to
+This operation is equivalent to
 @scheme[(not (zero? (bitwise-and n (arithmetic-shift 1 m))))],
-but is faster and runs in constant time when @scheme[n] is positive.
+but it is faster and runs in constant time when @scheme[n] is positive.
 
 @mz-examples[(bitwise-bit-set? 5 0) (bitwise-bit-set? 5 2) (bitwise-bit-set? -5 (expt 2 700))]}
 
@@ -605,7 +605,7 @@ but is faster and runs in constant time when @scheme[n] is positive.
 Extracts the bits between position @scheme[start] and @scheme[(- end 1)] (inclusive)
 from @scheme[n] and shifts them down to the least significant portion of the number.
 
-This is equivalent to this computation,
+This operation is equivalent to the computation
 
 @schemeblock[
 (bitwise-and (sub1 (arithmetic-shift 1 (- end start)))
@@ -616,8 +616,8 @@ but it runs in constant time when @scheme[n] is positive, @scheme[start] and
 @scheme[end] are fixnums, and @scheme[(- end start)] is no more than
 the maximum width of a fixnum.
 
-Each pair of examples below uses the same numbers, but shows the result in
-both binary and as integers.
+Each pair of examples below uses the same numbers, showing the result
+both in binary and as integers.
 
 @mz-examples[(format "~b" (bitwise-bit-field (string->number "1101" 2) 1 1))
              (bitwise-bit-field 13 1 1)
diff --git a/collects/scribblings/reference/sets.scrbl b/collects/scribblings/reference/sets.scrbl
index 1a6f35560c..5a137b6d7a 100644
--- a/collects/scribblings/reference/sets.scrbl
+++ b/collects/scribblings/reference/sets.scrbl
@@ -48,6 +48,12 @@ that they appear as @scheme[v]s, so in the first two cases, an earlier
 element that is @scheme[equal?] or @scheme[eqv?] but not @scheme[eq?]
 to a later element takes precedence over the later element.}
 
+
+@defproc[(set-empty? [set set?]) boolean?]{
+
+Returns @scheme[#t] if @scheme[set] has no members, @scheme[@f]
+otherwise.}
+
 @defproc[(set-member? [set set?] [v any/c]) boolean?]{
 
 Returns @scheme[#t] if @scheme[v] is in @scheme[set], @scheme[#f]