1.frightening 指 “吓人的；令人害怕的“：Ghosts are frightening .鬼怪让人恐惧.
2.frightened “感到害怕的；被吓得害怕了,受恐吓的”：
The frightened horse galloped away.受惊的马飞奔而去.
Many people are frightened of sharks.人们大都恐惧鲨鱼.
3.frightful 可怕的；讨厌的：
I was awakened by a frightful clap of thunder.
我被一声可怕的雷声惊醒.
These frightful experiences are branded on his memory.
这些可怕的经历深深印入他的记忆.