Ég set hreina bleyju og nýtt snuð í töskuna.

set is the 1st person singular present tense of setja, meaning to put / place / set.

So:

• ég set = I put / I am putting
• að setja = to put

In this sentence, Ég set ... í töskuna means I put ... into the bag.

A useful point for learners: Icelandic often uses the simple present where English might use either I put or I’m putting, depending on context.

They are both direct objects of the verb setja, so they appear in the accusative case.

• bleyja is a feminine noun

  • nominative singular: bleyja
  • accusative singular: bleyju

• snuð is a neuter noun

  • nominative singular: snuð
  • accusative singular: snuð
    (same form as nominative)

So:

• hreina bleyju = a clean diaper (accusative singular)
• nýtt snuð = a new pacifier (accusative singular)

This is very common in Icelandic: the verb controls the case of its object, and setja normally takes an accusative object.

Because adjectives in Icelandic must agree with the noun they describe in:

• gender
• number
• case

Here both nouns are singular accusative, but their genders are different:

• bleyja is feminine
• snuð is neuter

So the adjective changes form:

• hreinn → hreina with feminine accusative singular
• nýr → nýtt with neuter accusative singular

That is why you get:

• hreina bleyju
• nýtt snuð

This is one of the biggest differences from English, where adjectives usually do not change form.

Because í can take two different cases, depending on the meaning:

• accusative = movement into something
• dative = location in something

Here the sentence describes movement: the items are being put into the bag. So Icelandic uses the accusative:

• í töskuna = into the bag

Compare:

• Það er í töskunni. = It is in the bag.
  Here there is no movement, so dative is used.

This is a very important pattern in Icelandic prepositions.

The -na is the definite article, attached to the end of the noun.

So:

• taska = a bag
• töskuna = the bag (accusative singular)

Icelandic usually puts the definite article at the end of the noun rather than using a separate word like English the.

Also note the vowel change:

• taska → töskuna

That vowel change is part of the noun’s normal inflection.

Because they are indefinite here:

• hreina bleyju = a clean diaper
• nýtt snuð = a new pacifier

Icelandic often has no separate word for “a/an”. Indefiniteness is simply shown by the absence of the definite article.

So:

• bleyja = a diaper / diaper
• bleyjan = the diaper

The same applies to snuð.

Because í töskuna applies to the whole coordinated phrase:

• hreina bleyju og nýtt snuð

So the meaning is:

I put [a clean diaper and a new pacifier] into the bag.

You do not need to repeat the preposition before each noun unless you want special emphasis or a different structure.

This is natural Icelandic word order.

Yes, this is very normal Icelandic word order.

The structure is:

• Ég = subject
• set = verb
• hreina bleyju og nýtt snuð = direct object(s)
• í töskuna = prepositional phrase showing direction

So literally:

I put a clean diaper and a new pacifier into the bag.

This is a straightforward main-clause pattern in Icelandic.

Because og simply means and. It can connect words or phrases regardless of gender.

Here it joins:

• hreina bleyju (feminine noun phrase)
• nýtt snuð (neuter noun phrase)

Each adjective agrees with its own noun separately:

• hreina matches bleyju
• nýtt matches snuð

The conjunction og itself does not affect gender or case agreement.

A rough pronunciation guide for an English speaker is:

• Ég ≈ yeg
• set ≈ set
• hreina ≈ HRAY-na
• bleyju ≈ BLAY-yu
• og ≈ okh or og depending on speech
• nýtt ≈ neet (with a long ee sound)
• snuð ≈ snuuth (with ð like the th in this, though in final position it may sound weaker)
• í ≈ ee
• töskuna ≈ TUSK-u-na / TÖSK-u-na

A few useful pronunciation notes:

• ey in bleyju sounds like ay in day
• ý sounds like Icelandic ee-type vowel, not like English y
• ð is the letter eth, usually like voiced th
• hr at the start of hreina is a special Icelandic cluster that may feel unusual at first

Yes. Setja is a very common verb with a broad meaning: put, set, place, depending on context.

In this sentence, the most natural English translation is usually put:

• Ég set hreina bleyju og nýtt snuð í töskuna.
• I put a clean diaper and a new pacifier into the bag.

English often prefers put for everyday objects being placed somewhere, while set can sound a little more formal or specific depending on context.

The dictionary forms are:

• ég = I
• setja = to put
• hreinn = clean
• bleyja = diaper
• nýr = new
• snuð = pacifier / dummy
• í = in, into
• taska = bag

This is useful because the forms in the sentence are often inflected, so what you see is not always the exact dictionary form.

For example:

• set comes from setja
• hreina comes from hreinn
• nýtt comes from nýr
• töskuna comes from taska

You would change the case after í from accusative to dative.

So:

• í töskuna = into the bag (movement)
• í töskunni = in the bag (location)

Example:

• Ég set hreina bleyju og nýtt snuð í töskuna.
  I put a clean diaper and a new pacifier into the bag.

• Hrein bleyja og nýtt snuð eru í töskunni.
  A clean diaper and a new pacifier are in the bag.

This accusative/dative contrast with certain prepositions is one of the key patterns to learn in Icelandic.