1)Be sure of +抽象名词/doing sth ：主语是人，译为：主语有把握/确信…
He is sure of his success. = He is sure that he will succeed.
I’m sure of his honesty.
I’m sure of winning the game.
Be sure of + 反身代词 ：有自信心
She is not sure of herself .
2)be sure about +具体名词
I’m not sure about two things ——grammar and some of the idioms.
3)Be sure to do sth 主语可人可物、译为：说话人对句子主语的判断而不是主语对自身判断，译为：“主语一定、必然会…” He is sure to succeed.
It is sure to rain.
Be sure to do 用在祈使句中不表判断而是提出要求，肯定祈使句中译为“务必…/一定要…”， Be sure to forget it . 否定祈使句中译为“千万别做某事…” Be sure not to do that thing again.
4)Be sure + that 从句：主句主语对宾语从句中人或事的判断 “…确信某人/某事一定会…” I’m sure that you will make great progress this time . 5) sure 用作副词时常用于口语中 sure = of course / certainly