fill commands put two spaces after a colon.
@vindex fill-nobreak-predicate
- The variable @code{fill-nobreak-predicate} specifies additional
-conditions for where line-breaking is allowed. Its value is either
-@code{nil} or a Lisp function; the function is called with no
+ The variable @code{fill-nobreak-predicate} is a hook (an abnormal
+hook, @pxref{Hooks}) specifying additional conditions where
+line-breaking is not allowed. Each function is called with no
arguments, with point at a place where Emacs is considering breaking
-the line. If the function returns a non-@code{nil} value, then that's
+the line. If a function returns a non-@code{nil} value, then that's
a bad place to break the line. Two standard functions you can use are
@code{fill-single-word-nobreak-p} (don't break after the first word of
a sentence or before the last) and @code{fill-french-nobreak-p} (don't