Mac Office Word continually defaults to US English

Hi there,

I'm using Mac Office 2016 and I have set my default language to UK English. So as expected, when I create a new document, it says English (UK) at the bottom. However, when I copy text from another source such as the net or Libra Office, the language changes to English (US). Is there anyway I can force a document to stay English (US) or even better, delete the English (US) from my Mac?

I can't see the logic of it switching languages plus, if I copy a Canadian or Australian document or text, why doesn't it change to that language setting. Or better still, if I have an English (UK) document, and I copy/paste text and it switches to US, why doesn't it switch to UK when I copy/paste again from a UK format???

I've checked my System Preferences and I only have English (UK) language selected or, is there a way I can update the US dictionary so that I can update the 'z' words to 's' words to lessen the main problem I'm having with words, such as organization to organisation, analyze to analyse etc...

Apologies if in the wrong section as I couldn't find a section for Mac Software.

Thanks,

Maz