keep ones fingers crossed祈求成功
The leader was guilty of a serious dereliction of duty. He kept his fingers crossed that he could escape severe punishment.
let something slip through ones fingers眼睁睁地看着跑掉
The lawyer studied the case very carefully. He wouldnt let something slip through his fingers.
build a fire under someone紧催促某人
That guy is a slowpoke. I wish there were some way to build a fire under him.
put a fire under someone其主语一般是物，而不是人。
have other fish to fry有其他要紧事要做
Come on out! Forget about the exam, Youre got other fish to fry.
a flash in the pan昙花一现
He used to be called a young entrepreneur1. But soon he was forgotten by the public. He was a flash in the pan.
a fly in the ointment美中不足
Mobile phone are quite popular nowadays, but they ring at any time in the public areas. It is a fly in the ointment2.
be nobodys fool不傻，精明
You can not easily take him in. It is obvious that he is nobodys fool.
get off on the right foot开门红
Everything will go smoothly3 if we get off on the right foot.
put ones foot down气愤的表示反对
The boy wanted to quit school, but his father put his foot down.
play footsy with...与调情
Jack4 was so in love with Mary that he couldnt help playing footsies with her while having dinner.
marry a fortune嫁给了富豪
Scariet was in trouble, She wanted to marry a fortune and save the whole family.
as sly5 as a fox很狡猾
Though the suspect was as sly as fox, he had to admit his crime in front of solid evidence.
a dime6 a dozen数不清，不少
Pagers were rare ten years ago. Now they are a dime a dozen.
make free with...擅自用
Do you think Im a millionaire? Dont make free with my things.
a freeloader白吃白喝，爱占实惠的人
In America, even if you live with your relative, you cant be a freeloader.
a fair-weather friend不可以同患难的朋友
I have searched my conscience, and believe I have never mistreated you. But you turned out to be a fair-weather friend.
get stage fright怯场，紧张
The student got stage fright when he stepped into exam room.
add fuel to the flames火上浇油
The boy refused to make an apology to his father, which added fuel to the flames.