(defun foo1 ()              ; foo1は1つの引数をとり
    (interactive)           ;   単に2単語分前に移動する
    (forward-word 2))
     ⇒ foo1

(defun foo2 (n)             ; foo2は引数を1つとる
    (interactive "^p")      ;   引数は数引数
                            ; shift-select-modeでは、
                            ;   リージョンをアクティブにするか、拡張する
    (forward-word (* 2 n)))
     ⇒ foo2

(defun foo3 (n)             ; foo3は引数を1つとる
    (interactive "nCount:") ;   引数はミニバッファーで読み取られる
    (forward-word (* 2 n)))
     ⇒ foo3

(defun three-b (b1 b2 b3)
  "Select three existing buffers.
Put them into three windows, selecting the last one."

    (interactive "bBuffer1:\nbBuffer2:\nbBuffer3:")
    (delete-other-windows)
    (split-window (selected-window) 8)
    (switch-to-buffer b1)
    (other-window 1)
    (split-window (selected-window) 8)
    (switch-to-buffer b2)
    (other-window 1)
    (switch-to-buffer b3))
     ⇒ three-b

(three-b "*scratch*" "declarations.texi" "*mail*")
     ⇒ nil