Charly, sure to I'm not sure to say goodbye.... means....It is not certain that I will say goodbye. I'm sure to say goodbye....means......It is certain that I will say goodbye -------This has an objective sense. It does not mean that 'I am confident that I will say goodbye', it means, IT is certain. Just another one of those odd things in the English language. ( A long time ago, it had the subjective meaning of, I am confident that I will say goodbye.) sure about I'm not sure about saying goodbye....means...I have doubts about saying goodbye. I'm not confident about saying goodbye. I'm sure about saying goodbye....means....I am confident about saying goodbye. I am certain about saying goodbye.

"I'm not sure to say goodbye." - is that the person is not sure if he/she is leaving you(the person this is directed towards). It could also be spelled like this; "I can't decide whether or not to say goodbye". "I'm not sure about saying goodbye." - is that the person does not really want to say goodbye or doubts that it it's proper for the occasion.

hi, I'm not sure if that expression is really standard or you just heard it from someone...? however, Tormawk's explanation is okay. I just hope you heard the song "I can't find a words to say goodbye." :)

i think that the one who tells that want to express he's doubting to leave somewhere or somewho.