Ég kaupi skjá.

I buy a screen.

Breakdown of Ég kaupi skjá.

• ég: I
• kaupa: to buy
• skjárinn: the screen

Questions & Answers about Ég kaupi skjá.

Why is the verb kaupi and not kaupa?

Kaupa is the infinitive, meaning to buy. In the sentence, the verb has to match the subject ég (I), so it becomes the 1st person singular present tense: kaupi.

A useful mini-pattern is:

• ég kaupi — I buy
• þú kaupir — you buy
• hann/hún/það kaupir — he/she/it buys
• við kaupum — we buy
• þið kaupið — you (plural) buy
• þeir/þær/þau kaupa — they buy

So Ég kaupi skjá uses the correct present-tense form for I.

Why is it skjá instead of skjár?

Because skjá is the accusative singular form, and the direct object of kaupi takes the accusative.

• skjár = nominative singular, the basic dictionary form
• skjá = accusative singular, used here because it is what is being bought

So:

• Skjár er dýr. — The screen/monitor is expensive.
  Here skjár is the subject.
• Ég kaupi skjá. — I buy a screen/monitor.
  Here skjá is the object.

This is one of the most important things to get used to in Icelandic: noun endings often change depending on the noun’s role in the sentence.