"To take the piss" means to make fun of something, Leeneia.

'Unk' words aren't always nasty. Bunk beds are okay, and thick soup with big pieces of vegetables is often described as chunky. Then there are tuna chunks. A big chunk of something CAN be good. And I like to dunk my biscuits.

On the other hand there is flunk, slunk, stunk, drunk, and funk (a blue mood).

There are some not very nice 'Ank' words too.

Dank, lank, skank (dirty or promiscuous female), stank, wank, mank(y) (dirty or disgusting), spank, sank (well if your boat sank it wouldn't be nice), prank, etc etc.