Given the task definition and input, reply with output. In this task, you are given a paragraph, event and an entity. The event is part of the given paragraph and it changes the state of the entity. Your task is to classify the state of the entity into three classes: 1) not exist, 2) unknown location and 3) known location. "not exist" means the entity doesn't exist in that state anymore. "unknown location" means the entity exists in that state but location is unknown. "known location" means the entity exists and location is known. 

 "process paragraph : : Choose what you want to write your letter on. Think of what you want to say. Write some nice things!. Place the letter into an envelope. Put a stamp on the top right corner of the face of the envelope. Write the address of the recipient on the envelope. Put the envelope in your mailbox. Raise the flag on your mailbox, indicating to the mailman that you have outgoing mail. ", "event : Think of what you want to say.", "entity : envelope" 

 unknown location 