Both express fear, but one is more formal and lasting, and the other is more colloquial and can describe an instant fright.
Adjective. Feeling fear or worry about something. More formal, usually describes a continuous or deep fear. Only used predicatively: it comes after a verb, never before a noun.
She is afraid of flying.
Ella le tiene miedo a volar.
Are you afraid of the dark?
¿Le tienes miedo a la oscuridad?
He was afraid that he would fail the exam.
El tenia miedo de reprobar el examen.
Adjective. Feeling fear or fright. More colloquial, can describe both a sudden fright and general fear. Can appear before or after a noun.
The children were scared by the loud thunder.
Los ninos se asustaron con el trueno fuerte.
I was scared when I heard the strange noise at night.
Me asuste cuando oi el ruido extrano de noche.
She is a scared little puppy. Do not yell at her.
Es un cachorro asustado. No le grites.
Common mistake
Important grammar error: you cannot say "an afraid child". "Afraid" never goes before a noun. Correct: "a scared child" or "a frightened child". However, both work after a verb: "The child is afraid" and "The child is scared" are equally correct.
Trick to remember it
"Afraid" only goes after a verb (predicative). "Scared" can go before or after. If you need the adjective before a noun, always use "scared" or "frightened" to be safe.
Quick rule
Afraid = only after a verb ("she is afraid"). Scared = before or after a noun, more colloquial.
Did you know?
"Frightened" is a third formal synonym that works like "scared" (can go before or after a noun). "Terrified" indicates extreme fear. "Fearful" is very formal, almost literary. In daily conversation, "scared" is the most natural and versatile option.
Exercise 1 · Pick the right one
My little brother is _____ of spiders. He screams every time he sees one.
Exercise 2 · Pick the right one
We need to help the _____ animal before it runs into traffic.
Exercise 3 · Form the word
Afraid = only after a verb ("she is afraid"). Scared = before or after a noun, more colloquial.
Important grammar error: you cannot say "an afraid child". "Afraid" never goes before a noun. Correct: "a scared child" or "a frightened child". However, both work after a verb: "The child is afraid" and "The child is scared" are equally correct.
"Afraid" only goes after a verb (predicative). "Scared" can go before or after. If you need the adjective before a noun, always use "scared" or "frightened" to be safe.
Bryan López
Founder of SpeakUP Academy