Learn Hardcore Icelandic: Mamma er veik í dag.

Not necessarily. With close family members, Icelandic often omits the possessive when context is clear. Mamma er veik í dag naturally reads as “Mom is sick today.” If you want to be explicit or contrastive, say Mamma mín er veik í dag (“my mom”).

Why is Mamma capitalized here? Is it always capitalized?

It’s capitalized because it starts the sentence. Otherwise, mamma is lowercase. However, when used like a name (a specific person), it’s often capitalized in writing: Ég hringdi í Mömmu (“I called Mom”). Note the case form Mömmu.

Could I use Móðir instead of Mamma?

Yes, but it’s more formal. Móðir = “mother.” So you might hear Móðir mín er veik í dag, which sounds more formal/literary than Mamma mín er veik í dag.

What is going on in í dag? Why dag and not dagur?

Í governs either dative or accusative depending on meaning; in the time expression í dag it takes the accusative. Dagur (day) declines:

Nominative: dagur
Accusative: dag
Dative: degi
Genitive: dags So í dag literally “in day,” but idiomatically “today.”

Where can I put the time expression? Is the word order flexible?

Yes. Icelandic main clauses are verb-second (V2):

Neutral: Mamma er veik í dag.
Topicalized time: Í dag er mamma veik. In both, the finite verb er is in the second position of the clause.

How do I make it a yes/no question?

Put the verb first:

Er mamma veik í dag? Possible answers:
Já, mamma er veik í dag.
Nei, mamma er ekki veik í dag.

How do I negate it?

Place ekki after the verb and before the predicate:

Mamma er ekki veik í dag. (“Mom is not sick today”)

How does the adjective change with different subjects?

Masculine: Pabbi er veikur í dag. (“Dad is sick today.”)
Feminine: Mamma er veik í dag.
Neuter: Barnið er veikt í dag. (“The child is sick today.”)
Plural (mixed or masculine): Foreldrarnir eru veikir í dag. (“The parents are sick today.”)

What’s the difference between veik(ur), sjúkur, and lasinn?

veikur/veik/veikt: general “ill/sick,” common for temporary illness.
sjúkur/sjúk/sjúkt: “ill (with a disease),” more clinical/serious; also appears in idioms (e.g., sjúkur í “crazy about”).
lasinn/lasin/lasið: “ailing/under the weather,” often convalescent or mildly ill. Examples: Mamma er veik/lasin í dag.

How do I say “Mom got/became sick today”?

Use verða (“become”) in the past:

Mamma varð veik í dag.

How do I refer to someone else’s mom explicitly?

Add a possessive:

Mamma hans er veik í dag. (“His mom is sick today.”)
Mamma hennar er veik í dag. (“Her mom is sick today.”)
Formal: Móðir hans/hennar er veik í dag.
Plural their: Mamma þeirra / Móðir þeirra

Any quick pronunciation tips for this sentence?

Mamma: stress the first syllable; the double mm is long: roughly “MAHM-ma.”
er: like “ehr” with a tapped/flapped r.
veik: “vayk” (the ei is like English “ay”).
í: long “ee.”
dag: roughly “dagh,” with a softer, fricative-like g. Spoken as a chunk: í dag ≈ “ee-dagh.”

Why is there no article before mamma? Could I ever say “the mom”?

Icelandic has no indefinite article, and kinship terms used like names typically don’t take the definite article. You could say Mamman (“the mom”) in contexts where you mean a specific mother generically, but for “Mom” (yours), just Mamma is natural.

Is vera (“to be”) irregular? What are the present forms?

Yes, it’s irregular. Present tense:

ég er
þú ert
hann/hún/það er
við erum
þið eruð
þeir/þær/þau eru

How would I say “yesterday” or “tomorrow” in a similar sentence?

“yesterday”: í gær → Mamma var veik í gær.
“tomorrow”: á morgun → Mamma verður veik á morgun (if you mean “will be/becomes,” though predicting illness is unusual); more natural is with other verbs, but the time expression itself is á morgun.