1.frightened指的是受到惊吓的意思，一般指的是主观感受，主语是人，例如I was frightened，意思是我受到惊吓。
2.可以组成短语be frightened at，意思是对什么感到吃惊或害怕，例如I was frightened as she sound,意思是我听到这声音很害怕。
3.可以组成短语be too frightened to do something，意思是因害怕而不敢做某事，例如The boy was too frightened to move。
4.frightened后面可以接that从句，意思是害怕某事发生，例如I was frightened that he may have got lost in the mountain。