Norwegian nouns have three genders, and the definite is usually made in writing by adding the suffix -en for masculine, -a for feminine and -et for neuter (remember that the t is silent!). These suffixes are unstressed, and the e of -en and -et is pronounced as [ə]. It almost sounds like it’s not even there, yet the -n is always pronounced.
Masculine nouns that end with an -r in their indefinite form often go through an alteration of the pronunciation of the last vowel! Monosyllable nouns such as bror and far are pronounced [bɾuːɾ] and [fɑːɾ]. Notice what happens when they are definite: Broren is pronounced [bɾuːuɳ] and faren is pronounced [fɑːɑɳ]. A second vowel is added. There is a small pause in between the first and second vowel. The e of -en disappears completely, and the r and n merge to form a retroflex /ɳ/. As a foreigner, it is important to be aware of the distinction between [fɑːɑɳ] (faren) and [fɑːɑn] (faen), as the second word is used as a swear word.
Certain speakers of standard Eastern Norwegian turn feminine nouns into masculine nouns. Mor and jord (which are feminine nouns) will thus become [muːuɳ] and [juːuɳ] (if you pay close attention when you listen to these two words, you will notice that they have different tonemes). If they are kept feminine, the pronunciation is [muːɾɑ] and [juːɾɑ] (again, different tonemes). Attempting to speak the Oslo dialect and wanting to sound native, yet pronouncing these words *[muːɾen] or *[juːɾen] (incorrect in any Norwegian dialect! The closest you get is the Bergen dialect, but they use a guttural R similar to French or German: [muːʁɛn]) will give you away as a foreigner.
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