Using Vim to add something to the end of a series of a lines
I would like to use VIM to add something to the end of a series of lines. Ideally I could do something like add " X" (with a space before the X) to the end of lines 1-40 and 50-60 in a single command, i.e. ideally I could have a break in between where I didn't add something. If that's not possible just adding to 1-40 and 50-60 separately would work too.
I would be using bufdo to do this, but my understanding is that anything you can do in vim you can use with the bufdo command.
Thanks in advance!