Ég skrifa stutt minnisblað eftir fundinn og set upplýsingarnar í töflureikni.

Because ég takes the 1st person singular verb form.

• ég skrifa = I write
• hann/hún/það skrifar = he/she/it writes

With setja, the present tense is a little irregular:

• ég set = I put
• þú setur = you put
• hann/hún/það setur = he/she/it puts

So skrifa and set are the correct forms for ég.

It actually is in the accusative, because it is the direct object of skrifa, but many neuter singular nouns have the same form in the nominative and accusative.

So:

• nominative: minnisblað
• accusative: minnisblað

That is why it looks unchanged.

The adjective must agree with the noun in gender, number, and case.

minnisblað is:

• neuter
• singular
• accusative

So the adjective stuttur becomes stutt in that form.

That gives:

• stutt minnisblað = a short memo

This is a very common pattern in Icelandic: adjectives change form to match the noun.

Icelandic does not have an indefinite article like English a/an.

So:

• minnisblað can mean a memo
• töflureikni can mean a spreadsheet

If Icelandic wants to say the, it usually adds the definite article to the end of the noun instead.

Because Icelandic usually expresses the as a suffix, not as a separate word.

For example:

• fundur = meeting
• fundinn = the meeting in this case/form

And:

• upplýsingar = information / pieces of information
• upplýsingarnar = the information

The exact ending changes according to gender, number, and case, so the article does not always look the same.

Here eftir means after in a time sense, and in this use it takes the accusative.

So the noun fundur changes to the accusative definite form fundinn.

• eftir fundinn = after the meeting

This is something learners have to memorize with prepositions: Icelandic prepositions often require a specific case.

In Icelandic, upplýsingar is very often used in the plural where English uses singular information.

So a sentence like this naturally says:

• set upplýsingarnar í töflureikni

Even though the natural English translation may simply be put the information into a spreadsheet.

This is a good example of how noun number does not always match between English and Icelandic.

With í, Icelandic normally uses:

• accusative for motion into
• dative for location in

Here the verb set suggests putting something into a spreadsheet, so the grammar is accusative.

The tricky part is that töflureiknir has the same form töflureikni in both the singular accusative and singular dative. So even though the form looks the same, the function here is accusative.

Because both verbs have the same subject, Icelandic can leave the subject out in the second part, just like English can.

So:

• Ég skrifa ... og set ...

works just like:

• I write ... and put ...

You could repeat ég, but it is usually unnecessary unless you want extra emphasis.

Yes. Icelandic word order is fairly flexible, although this sentence has a very normal, neutral order.

For example, you could also say:

• Eftir fundinn skrifa ég stutt minnisblað og set upplýsingarnar í töflureikni.

That puts after the meeting first for emphasis. Notice that when something else comes first in a main clause, the verb still stays in the second position:

• Eftir fundinn
  • skrifa
    • ég

That verb-second pattern is an important feature of Icelandic word order.