A driver stopped his car on a street side to have a rest. As he lay down in the seat and closed his eyes, a person came up and knocked  at the window to ask the time. The driver opened his eyes and looked at his watch: "It's 8:05," he said. Then he went to sleep again. But soon he was waken up  again because a second person was knocking at the window. "Sir, do you know the time?" he asked. The driver looked at his watch again, and told him it was half past eight. In this way, the driver thought he could not have a good rest, so he wrote a short note  and stuck  it on the window for all to see. It said, "I don't know the time." Again, he lay down in the seat for his sleep. A few minutes later, a third person came and began to knock at the window, "Hey, sir," he said. "It's a quarter to nine." ,. Why did the driver write a note and stick it on the window?
Because he didn't want anybody to trouble him. Because he didn't know the time. Because he needed somebody to wake him up. Because he wanted somebody to tell him the time.