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Questions & Answers about Þriðji dagurinn er bestur.
Why does þriðji end with -i?
Þriðji is the masculine singular nominative form of the ordinal number “third.” In Icelandic, ordinals must agree in gender, number, and case with the noun they modify. Since dagurinn (“the day”) is masculine singular nominative, the ordinal takes the -i ending: þriðji.
Why does dagurinn end with -inn?
The base word is dagur (day). Adding -inn makes it definite (“the day”). In Icelandic you don’t use a separate word for “the,” but add a definite suffix. So dagur → dagurinn = “the day.”
Why do we say er bestur instead of just er best?
Bestur is the strong superlative form of the adjective góður (“good”), matching masculine singular nominative. In predicate position, adjectives still agree with the subject’s gender, number, and case, so you need -ur on bestur. Simply best would be indeclinable and is not correct here.
Could we say þriðji dagur er bestur without the -inn on dagurinn?
No. When you use an ordinal (like þriðji), the noun must be in the definite form. Omitting -inn would make dagur indefinite (“a third day”), which doesn’t match the meaning “the third day.” So you must say þriðji dagurinn.
How would you form other cases if you needed “of the third day” or “to the third day”?
You’d decline both words together:
• Genitive: þriðja dagsins (“of the third day”)
• Dative: þriðja degi (“to/for the third day”)
What’s the word order rule in Þriðji dagurinn er bestur?
Icelandic follows a V2 (verb-second) rule in main clauses. Here the copula er is the verb in second position; the subject Þriðji dagurinn comes first for emphasis. You could also say Dagurinn er þriðji bestur, but that would change the nuance.
How do you pronounce Þriðji dagurinn er bestur?
A rough phonetic guide:
“THRITH-yee DAH-gur-in nair BEH-stur”
• Þ = “th” as in thin
• ð = “th” as in this
• Stress on the first syllable of each word.
How would you say “the third-best day” (i.e. the day ranked third in awesomeness)?
You’d use the ordinal plus the superlative adjective before the noun:
þriðji besti dagurinn
Here þriðji (third) and besti (strong superlative agreeing with masculine nominative) both precede dagurinn.
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