31. （ ）

(单选题)John’s not been to New York, ______. (单选题)Somebody is knocking at the door; I wonder who ______ is. (单选题)Reading can satisfy ______ hunger that comes from the desire (单选题)He is a student of Tsinghua University, majoring ______ phys (单选题)People put these signs on the roads to ______. (单选题)A driver can leave his car ______. (单选题)At the places where you see sign 1, ______. (单选题)Andy is a Korean boy. Which book can he read? (单选题)Why does Alfie want to be an angel? (单选题)You ______.