''are you crazy ?''she asked him.
⇒ She asked him if he was crazy.
''will you be at the party?''he asked her.
⇒ He asked her if she would be at the party.
''can you meet me at the station ?''she asked me.
⇒ She asked me if I could meet her at the station.
''who known the answer ?''the teacher asked.
⇒ The teacher asked if anyone knew the answer.