Realizes

As he sits in the dark, typing away at his computer, he hears the sound of morning birds chirping away and realizes he has been up all night - but the insomniac still refuses to sleep.

The victim of blackmail has been paying hush money for years, but now he realizes it is foolish, and has decided not to pay a red cent more.

It won't be long before he realizes the mistake.

He realizes that public officials are human, and that as human beings they are capable of misjudgement.

He fully realizes that he was the cause of the accident.

I wonder if Tom realizes how many hours a day I work.

I wonder if Tom realizes how lonely I am.

I wonder if Mary realizes how poor Tom really is.

I don't think that Tom realizes how rude he's being.

My history teacher is awful: he begins talking of a topic, and then he starts digressing, and I think not even he realizes what he had explained.