Many years ago now I was best man at my brother's wedding. Because of the inter-cultural nature of this event (ie French speaking Belgian), I needed to do a speech in French in a context where the idea of the best man's speech was quite unfamiliar. I was caught by the mother of the bride a few moments before this desperately reading through my little cards - as I explained - trying to make sure that I didn't slip accidentally into Italian at any point.
Apparently, I made it - until the very last sentence, when I slipped into Italian.
Tonight - I couldn't wait - at the first participation in Mass in the new English translation a similar thing happened. I DID remember "The Word of the Lord" at the end of the reading I was asked to do. The very last "and with your spirit", just before the final blessing, was where I lost my concentration and let slip an "also with you".
Must try better next time!