podziemne

In a sentence

• Kopalnie są podziemne.

  The mines are underground.

  Here, 'podziemne' is an adjective describing the mines, denoting their location under the ground.

• Podziemne jest labirynt tuneli pod miastem.

  The labyrinth of tunnels under the city is underground.

  In this sentence, 'podziemne' characterizes the tunnels as being located below the surface underground.

• Istnieją podziemne źródła wody w tej okolicy.

  There are underground water sources in this area.

  Here, 'podziemne' modifies 'sources' (of water) to specify that these are found below ground level.