"the road signs which will be in two languages"

In Wales. Thought this was an Irish question?

My above answer links to this site which gives the basics for ROI, http://www.drivingschoolireland.com/contents.html

The main difference between Northern Ireland and Southern Ireland are the speeds given in MPH north and Kilometres Per Hour in the South. The North also uses £ Sterling rather than €uro in the South.

Maybe not in Northern Ireland. In Ireland the signs are in two languages