Most Danes have a fairly informal use of language.

The formal uses of du (you), i.e. De, Dem and Deres, are rarely used (mostly just for royalty or very senior citizens).

The use of Titles

In a formal context a gentleman is en herre (Hr. Andersen).

A lady is en dame (Fru. Andersen).

A younger unmarried lady is Frøken Andersen.

However, titles are really not used in Denmark anymore and people might even get offended if you address them with a title(!)

The 'F' word

Swearing is not censored on Danish TV and more than occasionally a swear word will pop up in Danes' conversations with each other.

However, it is strongly recommended not to be using foul language when starting your Danish journey. You never know who is listening..