Happy retirement! translates as Alles Gute für den Ruhestand.
"Maligayang pagreretiro" is how you say happy retirement in Tagalog.
Depending on the relationship with the person retiring, would determine what to say in a written Happy Retirement. If the relationship is not a close on, a simple "Congratulations and Happy Retirement" would be sufficient.
If you want to say happy retirement in Italian you would say, pensione felice. You would say good luck by saying buona fortuna.
"Feliz aposentadoria."
In Afrikaans, you can say "gelukkige aftrede" to wish someone a happy retirement.
Feliz jubilación! or simply "Felicidades!"
Assuming you mean "how" to say happy in German, there are a couple of different ways: Froh and gluecklich.
Happy Friday in German is glücklicher Freitag
In finnish: hyvää eläkettä
happy - glücklich Also fröhlich, froh
I am not a happy puppy is an English idiom and cannot be translated into German in a way that conveys it's meaning.
happy married life = glückliches Eheleben