While using bash there are many time you may need to copy an argument you have already typed. Instead of typing the argument again you can use the following shortcuts:
Ctrl-w
: cut the word before the cursor
Ctrl-u
: cut the part of the line before the cursor
Ctrl-y
: paste at cursor location
Now if you want to copy the second argument video.mkv at the end in the following line and add .orig:
$ cp video.mkv<Ctrl+w><Ctrl+y><space><Ctrl+y>
.orig
In a situation you need to run a command before the current one you already typed, use Ctrl-u to cut the whole line you typed, run the required command and again use Ctrl-y as:
$ vi myfile.c<Ctrl-u>
//to cut the whole line $ dos2unix myfile.c //run the command you missed $<Ctrl-y>
//copy back the old line