1.“板上钉钉的事”怎么说？可以说a done deal.比如, she hasn't said yes to his marriage proposal, so it's not a done deal.她还没接受他的求婚,所以还不是板上钉钉的事。或者Set in stone，这个俚语用来表示sth. is impossible to change，即某事物不可能改变了，某事是板上钉钉的了，如：The schedule isn't set in stone.口语里还可以说：Sure thing板上钉钉的事儿，如：It's a sure thing that he'll marry her.他娶她是板上钉钉的事儿。

　　2.“太贵了”怎么说？It's a rip-off.太宰人了。或者Highway Robbery“太贵了，简直就是抢钱”，比如Charging that much to see a movie is highway robbery!看场电影就收那么多钱简直是拦路抢钱啊！还可以说cost sb. an arm and a leg花了某人很多钱；3.break the bank用尽所有的钱It's too pricey.太贵了。It's beyond my budget.超出了我的预算。It's out of my price range.超过了我能负担的范畴。I cannot afford it.我负担不起。

　　3.“白菜价”怎么说？dirt cheap特别/相当的便宜，例如：Be careful when you buy dirt cheap clothes. They could shrink easily or the colors could run when you wash them.买廉价衣服时要注意，它们洗后容易缩水或容易掉色。I bought this dress on Taobao. It was dirt cheap.这件裙子在淘宝上买的，巨便宜。We're having a moving sale. Everything is dirt cheap.我们搬家前卖东西，所有东西都是白菜价。

　　4.“食言”怎么说？“食言”，谓之：不履行诺言，违背诺言，英文可以这么说：break (one's) word/promise, to fail to keep a promise，例如：He has broken his word so many times that no one can believe him any more.他已经食言太多次了以至于没人再会相信他了。注意，是break (one's) word，是word不是words哦。eat (one's) words, to have to take back one's statements; to confess that one's predictions were wrong即“收回前言”，承认之前的预言是错误的，例如：I was wrong about the game and had to eat my words.口语里还可以说：I take that back.我收回自己刚刚说的话（用于反悔或承认有错）。

　　5.“话到嘴边”怎么说？“话到嘴边突然忘了”我们应该都遇到过，英语里这么说：be on the tip of your tongue，意思是话到嘴边突然忘了，但是你觉得你能记起来的，例如：Now what's her name again? Hang on, it's on the tip of my tongue.她的名字叫什么来着？等等，话到嘴边突然想不起来了。