Search and replace in powershell using wildcards

Hi

I'm trying to figure out how to replace a some random (ish) text, in a text string with a defined piece of text using Powershell.

The text I want to replace is always between the same two words but the actual text varies from device to device.

Lets say the text line is 

Server this bit of text varies Language

I want to replace the text between "Server" and "Language" with "it will always say this"

I want to write something like this

so whatever is between Server and language is replaced with "it will always say this".

I realise I've not got the regular expression correct. Can anyone help?

Cheers

Alex