Learn Icelandic: Tímabilið eftir stríðið er erfitt. - The period after the war is difficult.

In the context of temporal expressions, eftir means 'after.' It is used to show that one thing follows another chronologically, working very much like it does in English. Here, it connects tímabilið (the period) to the event that happened before it, stríðið (the war).

How is the word tímabilið built?

It is a compound word made of tími (time) and bil (space or interval). Together, tímabil means a 'period of time' or 'era.' The -ið at the very end is the neuter definite article 'the,' making it 'the period.'

Why does the adjective erfitt (difficult) end in -t?

In Icelandic, adjectives must change their endings to match the gender of the noun they describe. Because erfitt is describing tímabilið (a neuter noun), it takes the neuter singular ending -t. If you were looking it up in a dictionary, you would find its base masculine form, erfiður.

Why isn't there a separate word for 'the' before the word for war?

Unlike in English, the definite article 'the' in Icelandic is attached as a suffix to the end of the noun. The base word is stríð (war), and adding the neuter definite suffix -ið creates stríðið (the war).