Learn Swedish: Nålarna är väldigt tunna. - The needles are very thin.

The base form for "thin" is tunn, which ends in a double 'n' to indicate that the 'u' is a short vowel. When adding the plural -a to make tunna, the double 'n' stays. However, in the neuter form (tunt), one 'n' is dropped because Swedish spelling rules usually avoid putting double consonants directly before a 't'.

Why does väldigt end in a -t here?

The base word väldig is an adjective originally meaning "huge" or "enormous". By adding a -t, it turns into the adverb väldigt, which is widely used in Swedish to mean "very". It takes the adverb form here because it describes how thin the needles are, modifying the adjective tunna rather than a noun.

Let's review noun endings. How is the word Nålarna built?

The root is the "en" word en nål (a needle). To make it plural, you add -ar to get nålar (needles). To make it "the needles" (definite plural), you add the suffix -na, resulting in nålarna.