tunnel portal

• 隧道口,隧道洞口

tunnel portal的用法和样例：

例句

1. He ran down the circular stairs and got to the entrance to the tunnel just as DeLisio got to the tower.
   就在德莱索上塔同时，他跑下旋转梯，奔隧道口而去。
2. Without the tunnel mouth being properly set up a derailed train will bounce off an invisible barrier when it tries to pass under the ground.
   如果没有适当的设置隧道口，一列出轨的列车将在进入隧道试图穿过地面进入地下时被看不见的栅栏弹回。