实用英语第4集

Traffic lights are signaling devices used to control the flow of traffic at intersections. They typically have three colors: red, yellow, and green. Red means stop, yellow signals caution or prepare to stop, and green indicates go. These lights help prevent accidents by ensuring that vehicles and pedestrians move safely and in an organized manner. Traffic lights are often placed at busy intersections or areas where controlled movement is needed to manage traffic and pedestrian flow.

A bridge is a structure built to cross over a gap, such as a river, road, or valley, allowing people, vehicles, or animals to cross from one side to the other. Bridges are made from materials like wood, steel, concrete, or stone and come in various designs, such as arch, beam, or suspension. They can range in size from small footbridges to large, multi-lane highway bridges. Bridges are important for transportation, connecting different areas and making travel easier and safer. They are also often considered engineering landmarks.

A church is a building used for Christian religious activities, such as worship, prayer, and community gatherings. It is typically designed to be a place where people come together to practice their faith, attend services, and celebrate religious holidays. Churches vary in size and architectural style, ranging from small chapels to large cathedrals. The interior often features seating for people, altars, and religious symbols like crosses or stained glass windows. Churches are also often important cultural and historical landmarks in communities.