Learn Swedish: Håret i nacken är bortrakat. - The hair on the neck is shaved off.

When a particle verb (like raka bort) is turned into a past participle used as an adjective, the particle must be attached to the front as a prefix. You would say han har rakat bort håret (he has shaved off the hair) as an active verb, but when describing the resulting state of the hair as an adjective, the particle is obligatorily prefixed to form the single word bortrakat.

Why does bortrakat end with a -t?

It is functioning as an adjective describing håret (the hair), which is an ett-word (neuter). Therefore, the past participle must take the neuter -t ending to agree with the noun. If you were describing a mustache (en mustasch), it would be bortrakad.

Why do we use the preposition i for "on the neck" instead of på?

Prepositions for body parts rarely map perfectly between English and Swedish. In Swedish, hair is said to be "in" the back of the neck (i nacken), whereas English says "on" the neck. It is best to memorize i nacken as a fixed idiomatic phrase.

Since "neck" is often translated as hals, why does this sentence use nacken?