Andy was a little country boy. He lived in the house on the side of a hill. There was a railroad track below the house and Andy often watched the train as it passed by.
One day, as Andy was crossing the track, he saw that there was something wrong with it. One of the rails seemed to be out of its place. Just then he heard a noise. Dear, dear! The train was coming! It would soon be there! He must try to stop it in some way.
Andy did not think of any danger to himself, but he ran and stood in the middle of the track, not far from the place where the rail was broken, and then he held out his arms and waited.
On and on came the train. The engineer saw the boy on the track and whistled for him to get out of the way. But Andy stood still and did not move.
The engineer had to stop the train. He was very angry as he cried out to the boy and asked him why he stood on track.
But when Andy pointed to the broken rail ，the man understood everything. Andy saved the train and the lives of all the people on it.
小题1:When Andy was young, _____.
A．he often liked playing at the foot of the hill
B．he often ran on the track up and down
C．he often enjoyed listening to the click of rails
D．he often watched the train pass by小题2:One day, as Andy went across the track, ____.
A．he thought there was something wrong with it
B．he saw the train was coming
C．he found one of the rails was broken
D．he heard a noise小题3:When the train was coming,____.
A．Andy stood on the track to hold out his arms
B．Andy ran to the train to stop it
C．Andy ran out of the track quickly
D．Andy cried out to the engineer小题4:As soon as the engineer saw the boy on the track,____.
A．he asked Andy why he stood there
B．he shouted at Andy
C．he whistled for Andy to leave the track
D．he asked Andy to get out of the way小题5:When Andy pointed to the broken rail,____.
A．the engineer got off the train and repaired it
B．the engineer understood and got very angry
C．the engineer understood why the boy tried to stop the train
D．the engineer came out to see what was the matter
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U=5×10-6×
×6 C=2×10-5 C上板带正电，电源提供的功率
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