Throw (or knock) someone for a loop: to confuse or shock someone, which usually makes the person very upset because he/she doesn’t expect it.
1). He threw me for a loop when he said he was quitting his job.
2). He totally threw me for a loop when he decided not to take my advice on the project we have been working on.
Get up on the wrong side of bed (or get out of the wrong side of bed, or wake up on the wrong side of bed): To seem grouchy on a particular day; to begin the day feeling unhappy and uncomfortable.
1). Did you get up on the wrong side of bed this morning? You are a real grouch! （你今天早上是不是发现你睡觉睡错边了？你是满腹牢骚。）
2). I got up on the wrong side of bed yesterday, and everything that could go wrong did! （我昨天可以说是万事不顺，所有可能出错的事都发生了。）
Out of gas:
1). Without gasoline (in a car, truck, etc)
2). Tired; exhausted; worn out
1). This car will be completely out of gas in a few more miles.
2). I have been playing tennis matches for more than three hours, and I’m really out of gas.
Ride the short bus: (this is an offensive and insulting idiom) to be mentally or physically challenged. The buses used by public school systems in US to transport mentally disabled children are generally half the size (or smaller) of the regular buses, thus the “Long Bus” for regular kids and the “Short Bus” for the special-ed kids.
a). That is a stupid idea and people would think you ride the short bus because of it.
b). You didn’t know who Barack Obama is? Did you ride the short bus to school?
Fly off the handle: lose one’s temper; get very angry
造句：He does not like tax, so don’t start any topics on taxes, otherwise he will fly off the handle.
Blow something or someone out of the water: to destroy or defeat something or someone completely.
This is the smartest idea I have ever seen and it blew all the rest ideas out of the water. （这是我所见过的最聪明的想法，完胜其他所有的想法。）
Full-court press: a very aggressive defensive strategy in basketball game in which the defense team pressures the offense opponent player-to-player in order to disrupt dribbling or passing. In business world, it usually is used to describe all-out effort.
a). If we want to submit the report by tomorrow, we have to make a full-court press on it now.
b). Suddenly behind by eighteen points, the coach asked the team to do a full-court press.
Be like a deer caught in the headlights: to be so frightened or surprised that you cannot move or think
Each time they asked him a question he was like a deer caught in the headlights. He really needs training on public speech.
Spill the beans: to give away a secret or surprise; to let secret information become known
这个常用口语的意思是泄密，暴露真相。有的时候也可以说spill the works，意思是一样的。
a). There is a surprise party for Jessica on Saturday. Please don’t spill the beans.
b). He has been trying hard not to spill the beans about his secret purchases.
a). A pat on the back: a word of praise, encouragement, or congratulations.
b). Pat on the back: to praise, encourage, or congratulate.
a). He has done a wonderful job on this project and he deserves a pat on the back.
b). Tristan’s mom patted him on the back for the cool sand castle he built.
会用了吧？现在去试试看吧to give someone a pat on the back，或者pat someone on the back。