a long passage under or through the ground, especially one made by people

The train went into the tunnel. 火车驶入隧道。

the long passage through which football, rugby etc. players walk to get to the pitch

to dig a tunnel

The decision has not yet been made whether to tunnel under the river or build a bridge over it. 还没有决定是在河底挖掘隧道还是在河上建桥。

The alternative is to tunnel a route through the mountain. 另一个办法是挖一条穿山隧道。

He was trapped in a collapsed building but managed to tunnel his way out. 他被困在倒塌的楼房下，但他想办法挖地道出来了。