Unexpected things may happen every day but no one can tell when and where. People usually

Unexpected things may happen every day but no one can tell when and where. People usually get surprised or frightened by such things. One day I __ 31__ a taxi to go to a meeting. As it came near the corner, the taxi stopped suddenly. The driver got out looking puzzled. A big truck which had been following the taxi stopped, too. The taxi driver was now standing at the corner looking up to the sky. And the truck driver got out and __ 32 __ him. A number of cars behind them were forced to stop as well and a large crowd of people had __ 33 __ at the corner.

The cause of all this __ 34 __ was a very strange noise. It sounded as if thousands of birds were chirping. The sound of so __ 35 __ birds together was quite surprising and many people looked __ 36 __. The most extraordinary thing was that, except one or two sparrows, there was not a bird in __ 37 __. No man was able to know why --- until two policemen arrived on the scene. They walked all around the area for a while and then __ 38 __ over near the rail-road tracks beside a big board advertisement for a __ 39 __. Since the noise seemed to be coming from around there, they climbed up and found that two loudspeakers had been hidden behind the advertisement. The bird noises were broadcast to __ 40 __ attention to the film advertisement. The cinema that made this advertisement was ordered to take the loudspeakers away, because they caused trouble and people were tired of them.

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