pay on the nail立即支付。這裡的nail指的並不是釘子，而是柱子。在古歐洲的交易市場和集市上，會用固定或是可搬移的柱子搭建平臺，讓人在上面談好價錢，並且一手交錢，一手交貨。pay on the nail就是指談妥價錢後，馬上付帳。
看看老外聊天時怎麼用pay on the nail：
Grace: Mr. Baker wants another 10% off.
Howard: That would leave us with almost nothing.
Grace: Exactly. But he is our important client.
Howard: Maybe we can try offering another 5% off.
Grace: Alright. I hope he can agree to pay on the nail.
格雷絲：貝克先生要求再降10%。
霍華德：那我們幾乎就沒有利潤了。
格雷絲：就是啊，但他是我們很重要的客戶。
霍華德：我們也許可以試著再降59給他。
格雷絲：好吧，希望他會同意成交。
pay on the nail例句精選：
We have to pay on the nail before we can leave with the goods.
我們必須當場付款，才能拿走貨物。
They're good customers who always pay on the nail.
他們是好主顧，付帳從不耽擱。
The shop will give a discount of ten per cent as long as you don't want credit but pay on the nail.
要是你不賒帳而即刻付錢，商店可以打9折。
Grace：I am sure this is the best price on the market.
Larry：I'd say if you gave me another 10%off，I would pay on the nail.
格雷絲：相信我，這是市場上最好的價格了。
拉裡：如果再降10%，我馬上結帳。
拓展學習：
payment 支付
discount 折扣
depreciation 跌價
rollback 削減
on the spot 立即；當場
pay in cash 現金支付
cost next to nothing 幾乎不用錢