Mr. Smith has bought a train ticket at the booking office. He still has some time before the train leaves, so he finds a seat and sits down. A few minutes later, he hears an announcement over the loudspeaker:

      "Attention, please. The 8:30 train to Philadelphia has a delay of 20 minutes. The 8:30 train is running about 20 minutes late. We apologize for any inconvenience it may cause."   

       
       It is his train. Mr. Smith has a look at his watch and continues to wait. When he hears the second announcement, he almost falls asleep. 

        "The 8:30 train to Philadelphia is now standing at Platform 5. Passengers are requested to board the train immediately." 
       
                                                                                       Mr. Smith gets to his feet happily and comes up to the ticket
                                                                               collector. He will soon be home.