Formal:
* Tem medo: This is the most literal translation and is the most formal way to say "are scared."
* Está com medo: This is slightly less formal than "tem medo" but still quite formal.
Informal:
* Está com medo: This is a common way to say "are scared" in informal contexts.
* Está apavorado: This means "terrified" and is very informal.
* Está com susto: This means "scared" but implies a sudden fright.
* Está com frio na barriga: Literally "having a cold stomach," this is a more idiomatic way to say "scared" and is quite informal.
Example sentences:
* Ele tem medo de altura. (He is scared of heights.)
* Ela está com medo do escuro. (She is scared of the dark.)
* Estou apavorado com essa tempestade. (I am terrified of this storm.)
* Estou com susto porque ouvi um barulho estranho. (I am scared because I heard a strange noise.)
* Estou com frio na barriga para a apresentação. (I am scared of the presentation.)
The best way to say "are scared" in Portuguese will depend on the specific situation and who you are talking to.