tunnel portal

例句：

1. 1.The tunnel portal is the first thing you see when you enter the underground parking lot.
   当你进入地下停车场时，首先看到的是隧道入口。
2. 2. The tunnel portal was designed to allow for easy access to the main road.
   隧道入口的设计是为了方便主路的通行。
3. 3.The tunnel portal was closed due to maintenance work.
   由于维护工作，隧道入口关闭了。