hello, does somebody knows why "lord of the dance" is traduced that way, with rince and tiarna switched?

i'd have another question. In the method I use, they say to do that :

Is + object (antecedent) + a + relative form of bí + subject + a + VN
(Is é) an obair atá Pól a dhéanamh = The work is done by Paul.

I found that strange. first, I think it would be rather "being done", and I am not convinced by the position of the () (how do you call them in english, i am french, maybe the parentheses).

thank you and good bye

"Rince na tiarna" is incorrect. It should be "Tiarna an rince".

"(Is é) an obair atá Pól a dhéanamh (ná) an seomra a ghlanadh" - the parentheses show that the "is é" can be omitted in speech. It describes a continuous (progressive) action in the immediate present: "The work that Pól is doing/is being done by Pól is cleaning the room".

You could also say the same thing in the following ways:

(Is é) an obair atá ag Pól á déanamh (ná) an seomra a ghlanadh
(Is é) an obair atá á déanamh ag Pól (ná) an seomra a ghlanadh

thank you! now it's clear

They probably meant to say -

Rince na dTiarnaí - The Lords' Dance

(as in more than one Lord dancing)

and is the sentence "(Is é) an obair atá Pól a dhéanamh" only correct?
I wonder as you added a complement, and it looks as the beggining of a relative.