Here is a detail when using '!!:n' with ':p' when trying to iteratively construct a complex command. I want to emphasize the use of the up-arrow (which will show the interpolated arguments), as opposed to rewriting exactly what you wrote in the previous command, since the usage of ':p' will be interpreted by the shell as a command in itself:

    $ echo a b c d
    a b c d
    $ echo !!:2:p
    echo b
    $ echo !!:2
    -bash: :2: bad word specifier # there was only 1 argument in last command

However:

    $ echo a b c d
    a b c d
    $ echo !!:2:p
    echo b
    $
    <up-arrow pressed once will give the following prompt> 
    $ echo b

I use magic-space for that in my inputrc:

  $if Bash
    Space: magic-space
  $endif

Basically does the same thing as :p, but after a space instead of enter.

Edit: fixed formatting.

  shopt -s histverify

to show the expanded command before executing it. Then just enter. I never get these right the first time.

In zsh, you can hit <tab> to expand it in place before hitting <enter>.