QUICK ANSWER
"Asustan" is a form of "asustar", a transitive verb which is often translated as "to frighten". Learn more about "asustar" below.
asustar(
ah
-
soos
-
tahr
)A transitive verb is a verb that requires a direct object (e.g., I bought a book.).
2. (to alarm)
a. to startle
Un grito espeluznante la asustó mientras dormía.A bloodcurdling scream startled her awake.
asustarse
A pronominal verb always uses a reflexive pronoun. (e.g., Te ves cansado.).
a. to get frightened
Nos asustamos muchísimo con la explosión de la bomba.We got terribly frightened when the bomb went off.
a. to get worried
Me asusté cuando me di cuenta de que era tarde y María todavía no había llegado.I got worried when I realized that it was late, and María had not arrived yet.
