Frighten the hell out of sb.
Scare the hell out of sb.
Frighten the shit out of sb.
Scare the shit out of sb.
Oh man! You scared the shit out of me! What’s your problem?
Don't sneak up on me like that, you frightened the hell out of me!
Scare sb. to death
I am scared to death every time when I hear him singing.
Be scared shitless (VERY RUDE)
I was scared shitless when I woke up to the sounds of an intruder in my house.
Scare sth./sb. away.
Don't make too much noise or you'll scare away the birds.
Freak out 惊讶，吃惊
He freaked out when hearing the news.