This play points towards a conception of time where once-mighty civilisations are overthrown and are replaced by other forces that displace the original language and culture of the original civlisation. This is of course, the central theme of the play, as the Gaelic culture and language looks very much as if it will be vanquished by the English culture and language that is taking over Ireland. Time, then, is presented as a force that brings "translations" with it, both as a natural response to colonisation as one nation takes over another, as it literally "translates" itself, but also as the language of the original place becomes replaced with the language of the colonising force, and needs to be "translated" to. Time is something that is shown to bring great change and eventually to dismiss once vibrant and powerful cultures into obscurity.
You might like to think about the variety of allusions that are made throughout the play that refer to ancient languages or places. These allusions help to reinforce the description of time as something that commits cultures and civilisations into the past. In particular, Hugh's analogy compares Baile Beag to Carthage at the end of the play, another urbs antiqua (ancient city) as Virgil refered to it. The implication is clear: just as happened in Carthage, so will happen in Baile Beag as colonisers will come and commit the culture and language into obscurity.