be sure about something
be sure of something

But she was no longer sure of much about the future.

I think we are not sure about all this yet.

You could never be sure what she was going to feel, do or say about anything.

I often met people who were very sure about everything.

I'm not so sure about your idea for the long list.

They came to a part where he was not quite sure about the way.

What do you want to be sure about more than that?

Some certainly are, but can we be sure about all of them?

I wasn't sure about many things when it came to me.

At present we are not always sure about that, and want the country to move ahead.