you guys can check this link to understand the differences between sitter and setter, legger and ligger! http://norskstudy.blogspot.com.tr/2015/08/different-between-sittersetter-and.html
It depends on dialect, how fast the word is said, and whether it's a formal occasion which calls for more proper enunciation, but the "e" in "-en" usually ranges from faint to inaudible.
Similarly, the "t" in "-et" will usually be silent.
The "a" in the definite feminine ending "-a" should be pronounced.
You use "ned" with verbs indicating movement, and "nede" for static location. So it's "ned" for the process of getting seated, and "nede" to describe where you are seated.
This same pattern holds true for quite a few other adverb pairs like "opp/oppe" and "bort/borte", and a neat way I've seen for remembering which is which, is to imagine that the last "e" is so loosely fastened to the rest of the word, that it falls off whenever it starts moving.
Although "to sit" is most frequently an intransitive verb, in Western Canada, it is also a transitive verb -- used in colloquial speech. It is very common to hear, "Sit yourself down!" whereas "Set yourself down", is virtually unheard. Because "ned" need not be translated into English for the essence of the message to be conveyed, the translation that would, to most people sound both usual and correct is, 'The man is sitting himself in (or into) the chair."
Almost invariably, Western Canadians, use "sit" in reference to an action taken by a person (or an animal) affecting himself/ herself/ itself and not in respect to an action affecting another person or thing whereas they use "set" in reference to an action that an individual (or an animal) takes in respect to someone or something else. Example, "He set the plates on the table."