May life give you nothing but the best it has to offer which is exactly what you have given us as our teacher. Happy birthday.
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My career has been a challenging and enjoyable ride because you were there to guide me all throughout. Wonderful birthday!
It is always you who lead is into the right direction of success, now it is time for us to lead you on the right direction to the pub. Best birthday!
I wish you all the success and happiness that you deserve, plus a raise on my pay if you are feeling particularly generous today. Happy birthday!