tunnel cross section

例句：

1. 1. Thetunnel was constructed to provide a safe passagefor people during emergencies.
   这个隧道是为了在紧急情况下为人们提供安全的通行通道而建造的。
2. 2. The tunnelcross section is crucial forthe construction of the underground railwaysystem.
   隧道横截面对于地下铁路系统的建设至关重要。
3. 3. The tunnel cross section is measuredby the width and height of the tunnel.
   隧道横截面是通过测量隧道的宽度和高度来计算的。