Handritið er gott.

Because Icelandic usually adds the definite article to the end of the noun instead of using a separate word like the.

• handrit = manuscript
• handritið = the manuscript

The ending -ið here is the definite article for a neuter singular noun in the nominative.

You usually learn the gender as part of the noun. In dictionaries, Icelandic nouns are normally marked as:

• m. = masculine
• f. = feminine
• n. = neuter

Handrit is a neuter noun, and that affects:

• the form of the definite article: handritið
• the form of the adjective: gott

So the gender of the noun controls agreement in the sentence.

Because adjectives in Icelandic must agree with the noun they describe in gender, number, and case.

Since handritið is:

• neuter
• singular
• nominative

the adjective must also be in the neuter singular nominative form:

• masculine: góður
• feminine: góð
• neuter: gott

So Handritið er gott is correct because gott matches handritið.

Here the adjective is not directly attached to the noun. It comes after the verb er because it is a predicate adjective.

Structure:

• Handritið = subject
• er = is
• gott = adjective describing the subject

This is like English:

• The manuscript is good.

If you wanted the adjective directly before the noun, that would be a different structure, like the good manuscript.

Er is the present tense, third-person singular form of the verb vera (to be).

So:

• ég er = I am
• þú ert = you are
• hann/hún/það er = he/she/it is

In Handritið er gott, er means is.

Yes, in this sentence it is very similar:

• Handritið = subject
• er = verb
• gott = complement

So the pattern is:

Subject + verb + adjective

That said, Icelandic word order can be more flexible than English in other kinds of sentences, especially because of case marking and the verb-second tendency in main clauses.

A simple learner-friendly approximation is:

HAN-dri-thith er gott

A few useful notes:

• ð is like the th in this
• þ (not used here, but common in Icelandic) is like the th in thing
• ll, rn, nn, and some other combinations can have special pronunciations in Icelandic, but nothing especially tricky is happening in this sentence besides ð

The exact Icelandic pronunciation is more subtle than English spelling can show, but that approximation is a reasonable start.

Because Icelandic usually expresses the with a suffix attached to the noun.

So instead of:

• separate article + noun

Icelandic often uses:

• noun + definite ending

Examples:

• handrit = manuscript
• handritið = the manuscript

This is one of the first big differences English speakers notice.

It is in the nominative singular.

Why nominative? Because it is the subject of the sentence.

Why singular? Because it refers to one manuscript.

Why neuter? Because handrit is a neuter noun.

So the full description is:

• neuter singular nominative

And that is why the adjective also appears as gott.

Yes. Both the noun and the adjective would change to plural forms.

Singular:

• Handritið er gott. = The manuscript is good.

Plural:

• Handritin eru góð. = The manuscripts are good.

Changes:

• handritið → handritin (the manuscript → the manuscripts)
• er → eru (is → are)
• gott → góð (adjective agreeing with a neuter plural noun)

Yes. Like good in English, góður/góð/gott can have a range of meanings depending on context, such as:

• good in quality
• suitable
• pleasant
• morally good
• satisfactory

In this sentence, gott most naturally means something like good or of good quality. The exact nuance depends on context.

Eventually, yes, but at the beginning you mainly need to understand the basic agreement pattern.

A useful first step is to learn the nominative singular forms:

• góður = masculine
• góð = feminine
• gott = neuter

Then later you can expand to plural and other cases. Icelandic adjectives have many forms, but learning them gradually is much more manageable than trying to memorize everything at once.