nora 用英语:

Wolves usually use badgers' or foxes' burrows as breeding dens.

rabits burrowed underneath the fence

The world is a den of crazies.

We have a computer in the den.

Do you remember, that we used to play next to fox's den, when we were young.

lion’s den

The polar bear cubs emerge from the den in which they were born. The children had their special den, but they wouldn't tell anyone where it is.

make a den