Questions & Answers about Mánudagurinn er rólegur í dag.
The ending -urinn is the definite article (the) attached to the noun.
- mánudagur = Monday (indefinite: “a Monday / Monday”)
- mánudagurinn = the Monday (definite: “the Monday”)
In this sentence, Mánudagurinn means “this Monday / the Monday (today)”, the specific Monday you are talking about.
Icelandic usually sticks the article onto the end of the noun instead of putting a separate word in front, as English does with the.
You normally would not say Mánudagur er rólegur í dag in this context.
- Mánudagurinn er rólegur í dag = “The Monday (today) is quiet.”
- Mánudagur er rólegur í dag would sound more like “A Monday is quiet today”, which is odd and not how you talk about today’s Monday.
If you want to talk about Mondays in general, you would say for example:
- Mánudagar eru rólegir. – Mondays are quiet.
- Á mánudögum er rólegt. – On Mondays it is quiet.
Mánudagurinn is in the nominative case.