mail-abbrev-next-line
mail-abbrev-next-line is an interactive compiled Lisp function in `mailabbrev.el
'.
(mail-abbrev-next-line &optional ARG)
Expand a mail abbrev before point, then move vertically down ARG lines.
This only expands an abbrev (if one is present) if called with
point at the end of a line, or on whitespace before the end of a line.
In terms of line motion, this behaves like `next-line', which see.