Good night
In the Romance languages, "Good night" tends to imply that someone is off to bed, at least as soon as they get home. We'll talk about what you usually say instead with the next couple word items. But since we already know the words, we're going to do this one first.
Note that it works pretty much like "Good day": good + night in Fr. and It., good(s) nights in Sp.
French bonne nuit... stays Bonne nuit (bun nwee) - this one doesn't smoosh together.
Italian buona notte becomes Buonanotte (bwohna-noh-teh).
Spanish "Good night" is Buenas noches.
Incidentally, you should now see why I taught you masculine and feminine and singular and plural right from the beginning - even the greetings are just goofy syllables before you know about them, but once you've learned about them the greetings will make sense and will give you good patterns for keeping the grammar straight in turn.