Something that is underground is below the surface of the ground.
an underground parking garage for 2,100 vehicles.
一座能停放2100辆车的地下停车库。
Underground groups and activities are secret because their purpose is to oppose the government and they are illegal.
the underground Kashmir Liberation Front.
秘密的克什米尔解放阵线。
Something that is underground is below the surface of the ground.
Solid low-level waste will be disposed of deep underground.
低放射性固体废物将被弃置在地下深处。
If you go underground, you hide from the authorities or the police because your political ideas or activities are illegal.
After the violent clashes of 1981 they either went underground or left the country.
1981年的暴力冲突之后,他们要么转入了地下,要么离开了这个国家。
The underground in a city is the railway system in which electric trains travel below the ground in tunnels.