"They are only lawyers."
Translation:Níl iontu ach dlíodóirí.
I don't understand the use of Nil in front of the sentence. You are stating what they are not what they are not.
It's the common Irish structure for saying "only" (or in this case "just"). Níl ach cúpla focal Gaeilge agam. "I only have a few words of Irish.", i.e. "I only speak a little Irish." Níl ach trí euro i mo phóca. = "I only have 3 euros in my pocket."
If you speak Southern American English, it'd be something like 'They aren't but lawyers.' It's just a better generap English translation that's given.