题目

In the early hours of the morning, Gary Miller was in his truck, traveling down the road alone to deliver. Everything seemed calm. But with the sound of a fire siren (警笛) cutting through the wind, he became alarmed. Miller, a trucker by trade, has been a volunteer firefighter for 40 years. That loud, sharp siren assured him that help was on the way.Most people never realize that this help is often a crew of volunteer firefighters. They make up 70 percent of the country’s nearly 1.2 million firefighters. “When I was a teenager there would be many who responded. About 20 people were comi信息技术产业是美国对经济发展贡献最大的高新技术产业．概括美国信息技术产业对经济发展的主要促进作用。