Learn Icelandic: Kennarinn er ungur og hann er ekki þreyttur. - The teacher is young and he is not tired.

In simple Icelandic sentences, ekki (not) is placed right after the verb. Here it comes immediately after er (is). This happens to match English perfectly for the verb 'to be', but remember that ekki always follows the verb in Icelandic, even for action verbs where English would use 'do not'.

Why do both adjectives, ungur and þreyttur, end in -ur?

Adjectives in Icelandic change their endings to match the noun they describe. Because kennari (teacher) is a grammatically masculine word, the adjectives describing the teacher must be in the masculine singular form. For many adjectives, this masculine form ends in -ur.

How do we know this means 'the' teacher and not just 'a' teacher?

Instead of using a separate word for 'the' before a noun, Icelandic attaches an ending directly to the noun itself. The base word is kennari (a teacher). By adding the suffix -nn to the end, it becomes kennarinn (the teacher).

Why does the sentence use hann (he) for the teacher?

The noun kennari is grammatically masculine. In Icelandic, it is very common to use a pronoun that matches the grammatical gender of the word it refers back to. Therefore, hann is used here because kennari is a masculine word.