Duplicate set of characters and add to end of same line using PowerShell

Using PowerShell need to copy a single line and then paste it self over again right behind it.

Example is that it is a set of keywords that are being dynamically driven and then number is always going to change.  Due to this I need to make an update to one of the script but need to duplicate the number that it is spitting out.

So,

0000

0001

0002

0003

as my example

What I wasn’t is

0000 0000

0001 0001

0002 0002

0003 0003

I tried using

| for each { $_ + “ some value”}| could not get the “some value“ to be correct.

Any help would be great I am sure this is easy and just overlooking something simple.

thank you