完形填空
　　One afternoon two policemen sat in a car by a straight road in Australia. They were    1   the traffic and looking for a stolen car. One of the policemen who was driving the car saw a small plane flying    2    them. He followed it for a few minutes because it was very    3   . When the plane flew near to the police car, the driver saw something    4    from it and land in a    5    by the road. He got out of the car and walked across the field. He saw a wallet   6   the ground and  7    it up. Inside the wallet there was a note which    8   , “Oil nearly   9   . I have to land on the road. Please    10    the traffic. ”