英语问题：求be sure用法？

sb. be sure to do 说话人认为sb.一定会做某事
sb. be sure of / about sth. 说话人认为sb.确认,知道某事
sb. be sure that+从句 sb.认为某事(即that后面的句子)一定会发生
记住没有it is sure to do / that / of / about

be sure to do一般指别人认为主语可以做某事
be sure of doing一般指主语自己认为可以做到某事
You're sure to win the competition.
I'm sure of passing the exam