Genitive Measure Phrases
In English, we often use hyphenated phrases to describe measurements, like "a two-week vacation" or "a three-year degree". In Icelandic, you express this using the genitive (possessive) case. You are literally saying "a vacation of two weeks".
To build these phrases, both the number and the unit of measurement must be in the genitive case, placed directly before the noun they modify.
Numbers and Units in the Genitive
Before you can build these phrases, you need to know how to form them. The numbers 1 through 4 decline in Icelandic. For measure phrases, you will need their genitive forms: eins (one), tveggja (two), þriggja (three), and fjögurra (four).
You will also need the genitive plural forms of common time units:
- ár becomes ára (years)
- mánuður becomes mánaða (months)
- vika becomes vikna (weeks)
Work Schedules and Higher Numbers
This grammar pattern is extremely common when discussing job requirements, probationary periods (reynslutíminn), and work schedules (vinnuvikan).
When you use numbers five and higher, they generally do not change form in this context (such as fimm, sex, or tíu). Let's look at a few more time units in their genitive plural forms:
- dagur becomes daga (days)
- klukkutími becomes klukkutíma (hours)
- mínúta becomes mínútna (minutes)