fixed docs for lang

svn: r11351

collects/scribblings/htdp-langs/advanced.scrbl

@@ -241,13 +241,13 @@ choice provides an answer @scheme[expr] whose value is the result of
 the whole @scheme[case] expression. If none of the lines contains a
 matching choice, it is an error.}
 
-@defform/none[#:literals (cond else)
-              (cond expr [(choice ...) expr] ... [else expr])]{
+@defform/none[#:literals (case else)
+              (case expr [(choice ...) expr] ... [else expr])]{
 
 This form of @scheme[case] is similar to the prior one, except that
 the final @scheme[else] clause is always taken if no prior line
 contains a choice matching the value of the initial @scheme[expr]. In
-other words, so there is no possibility to ``fall off them end'' of
+other words, so there is no possibility to ``fall off the end'' of
 the @scheme[case] form.}
 
 @; ----------------------------------------------------------------------

collects/scribblings/htdp-langs/beginner.scrbl

@@ -169,7 +169,7 @@ evaluates to @scheme[true], it is also an error.}
 This form of @scheme[cond] is similar to the prior one, except that
 the final @scheme[else] clause is always taken if no prior line's test
 expression evaluates to @scheme[true]. In other words, @scheme[else]
-acts like @scheme[true], so there is no possibility to ``fall off them
+acts like @scheme[true], so there is no possibility to ``fall off the
 end'' of the @scheme[cond] form.}
 
 @defidform[else]{