Læknirinn skoðar handlegginn minn aftur á morgun.

The ending -inn is the definite article attached to the noun, like the in English.

• læknir = doctor

• læknirinn = the doctor

• handleggur = arm
• handlegginn = the arm

In Icelandic, the definite article is usually added to the end of the noun instead of standing as a separate word.

Because læknirinn is the subject of the sentence and it refers to a specific doctor: the doctor.

If you said læknir skoðar..., that would mean something more like a doctor examines... or doctor examines..., which is less natural here unless the context is very different.

In Icelandic, when a noun has a possessive like minn (my), it is very common to keep the noun definite as well.

So:

• handlegginn minn = my arm

This may feel strange to an English speaker, because English usually does not say the my arm. But Icelandic often uses both the definite form and the possessive together.

That is the normal Icelandic pattern in this kind of phrase:

• handlegginn minn = my arm
• literally: the arm my

Possessive pronouns such as minn, þinn, hans, hennar often come after the noun in ordinary usage.

This is one of the most noticeable differences from English word order.

Handlegginn is in the accusative singular masculine.

It is accusative because it is the direct object of skoðar (examines / looks at in this context). The doctor is examining the arm, so the arm is the object.

Basic pattern:

• læknirinn = subject, nominative
• skoðar = verb
• handlegginn minn = direct object, accusative

Minn agrees with the noun it belongs to.

Here it matches handlegginn, which is:

• masculine
• singular
• accusative

So the correct form is minn.

The possessive minn changes form depending on gender, number, and case. For example:

• masculine accusative singular: minn
• feminine accusative singular: mína
• neuter accusative singular: mitt

So handlegginn minn is grammatically matched.

Skoðar is the present tense, 3rd person singular form of skoða.

The subject is læknirinn = the doctor, which is he/she examines, so Icelandic uses:

• ég skoða = I examine
• þú skoðar = you examine
• hann/hún skoðar = he/she examines

So læknirinn skoðar means the doctor examines or is examining, depending on context.

Here aftur means again.

So the idea is that the doctor will examine the arm again tomorrow.

The word aftur can also mean back in other contexts, but in this sentence again is the natural meaning.

Á morgun is a very common Icelandic expression meaning tomorrow.

Literally, it looks like:

• á = on
• morgun = morning

But as a fixed expression, it simply means tomorrow.

So you should learn á morgun as a set phrase rather than translating it word-for-word every time.

That is a very natural neutral word order in Icelandic.

The sentence is organized like this:

• Læknirinn = subject
• skoðar = verb
• handlegginn minn = object
• aftur = adverb
• á morgun = time expression

Icelandic is fairly flexible with word order, but this version sounds normal and straightforward.

You could move things for emphasis. For example:

• Á morgun skoðar læknirinn handlegginn minn aftur.

Because Icelandic is a verb-second language, when Á morgun comes first, the verb skoðar must come next.

Yes. The Icelandic present tense often covers both a simple present and a future meaning when the context makes the future clear.

Because the sentence includes á morgun (tomorrow), English usually translates it with a future idea:

• The doctor will examine my arm again tomorrow.

But grammatically, Icelandic is still using the present tense form skoðar.

The case endings help show that.

• læknirinn is the subject form here
• handlegginn is the object form here

So even if word order changes, the endings often help you understand the roles.

In this sentence:

• the doctor does the examining
• my arm receives the action

That is one reason Icelandic pays so much attention to noun forms and case.