怖い

1. Origins, structure, and basic meaning

• Structure: 怖い (こわい) is an adjective for fear caused by danger or uncertainty. It appears as general judgment and past experience.
• Basic usage: Walking alone in a night forest is frightening; a loud sound causes brief fear.

2. Common pitfalls and similar expressions

• Fear of a situation and momentary reaction to sound
  • The first evaluates a nominalized action; the second cause is 大きな音がして. Distinguish feared situation and experiencer.