Hun er følsom for støy.

It is a very common pattern meaning sensitive to or easily affected by something.

So følsom for støy means that noise affects her strongly, bothers her easily, or is hard for her to tolerate. It does not have to mean a medical condition; it can also just describe a personal trait.

Because Norwegian and English do not always match prepositions.

With følsom, Norwegian normally uses for:

• følsom for støy
• følsom for lys
• følsom for kritikk

So this is something you mostly have to learn as a set pattern: følsom for + noun.

Because støy is usually an uncountable noun, like English noise.

In a general statement, Norwegian often uses the noun without an article:

• følsom for støy = sensitive to noise in general

If you mean a specific noise, you can make it definite:

• Hun er følsom for støyen fra trafikken.

Lyd means sound in general.

Støy means noise, especially unwanted or disturbing sound.

So:

• lyd = neutral word
• støy = negative or disturbing sound

That is why støy fits well here. It suggests that the sound is intrusive or unpleasant, not just any sound at all.

Because adjectives in Norwegian agree with gender and number.

Here, the subject is hun, meaning one person, so the adjective takes the basic singular form følsom.

Compare:

• Hun er følsom.
• Det er følsomt.
• De er følsomme.

So følsom is the correct form with hun.

Yes.

Å være = to be
er = is / am / are in the present tense

So this sentence is in the present tense and describes her current state or a general characteristic.

Yes, absolutely.

Støyfølsom is a compound adjective meaning noise-sensitive. Norwegian uses compounds very often, so this is natural.

Both are good:

• Hun er følsom for støy.
• Hun er støyfølsom.

The compound version can sound a little more compact or slightly more technical, but both are common and correct.

Sometimes, but følsom is the more natural choice here.

Sensitiv does exist in Norwegian, but it is often used in more specific contexts, for example:

• sensitiv hud
• sensitiv informasjon

For a person reacting strongly to noise, følsom for støy or støyfølsom sounds more idiomatic.

It is one syllable.

The tricky part is øy, which has no exact English equivalent. A rough guide is:

• start with a rounded vowel sound
• glide slightly toward an ee-like ending

So støy is not pronounced like English toy, even though that may be a tempting guess.

No, this is the normal main-clause order:

• Hun = subject
• er = verb
• følsom for støy = complement

So it follows a simple pattern:

Subject + verb + description

If you move another element to the front, Norwegian still keeps the verb in second position:

• I store folkemengder er hun følsom for støy.

That verb-second pattern is very important in Norwegian main clauses.