know of something **

I know of no other world to which to go.

He already knew the answer to the question, of course.

Do you even know of anyone who has gone to work or to school every day?

But student services knew of the situation, from the student's side at least.

My family, and all I knew of love as a child.

He and his wife care only about themselves, from what I know of them.

I do not really know very much of these things.

But in the long run, I don't know of any other way to market a service like his.

I know of several other parents who have made the same decision.

But he was dead What did they know of her son?