What is the difference between ‘ancient regime’ and ‘ancien regime’?
“Ancien Régime” is French, and refers to an old social and political system in France; see en.wikipedia.org/wiki/Ancien_regime
“ancient regime” is a generic English phrase that just means what it says.
Although the two words are clearly cognate, “ancien” in French means something more like “old” or “former” than the English “ancient”.
- Hindi and Urdu are cognate languages.
- Hindi and Urdu languages are closely akin to one another.
Are these two sentences OK?
I would use the definite article with (2):
The Hindi and Urdu languages are…
I would also probably not bother with ‘languages’ in (2) if the context made it clear:
Hindi and Urdu are …