In 1912 Gaffet A．Morga was worried about the large number of fires in the factory of his city．He wanted to make something that would protect the people who had to fight the fire. They were often hurt．Sometimes they were killed by gas and smoke．They needed something that would help them put out fires quickly and safely．

    Morgan developed the safety hood（头罩）. It was a hood to be worn over the face. Two tubes ran down the back leading to an air trap（空气收集器）of clean air below．This hood allowed the firefighters to remain in smoke-filled rooms longer and with less danger.

On July 25．Cleveland，Ohio was rocked（震撼）by an explosion（爆炸）．The explosion trapped（困住）thirty-two workers in a tunnel（隧道）under Lake Erie. Morgan was called to help．Morgan and his brother，Frank，and two other men put on safety hoods. They went into the tunnel．They brought out all the workers．who were still alive．For his help，Morgan received medals（奖牌）from the city of Cleveland and the International Association of Fire Engineers．

    Morgan improved this safety hood in 1917 T11e11 in 1923，he made something else to help make the world safer for people．Morgan invented the first electric traffic signal.

1．What led to the invention of the safety hood?

2．What is paragraph two mainly about?

3．Why was Morgan called to help the people trapped in the tunnel?

4．How many people went into the tunnel except Morgan?

5．What was invented in 1923 by Morgan?