what is the old man sitting on?怎么回答?

what does the old man doing?和what is the old man doing?哪句正确? ( )is the old man? ( )is the old man? How old the man is!(用What问） what is the old man sitting on?怎么回答? Who is the old man? What is the man? the old man is ___for the beach the old man is（ ninety years old?） 提问 （）（ ）is the old man What is the old man___________? The old man in the car is an old teacher. Is the old man (空格) grandfather? The old man is ___ ill .( terrible) Look!The old man is e____. Old man is the twice of Is the old man a____or dead? The young man is behind the old man. what is the man doing