Once I had this question and I got some nice hints about it. Unfortunately, it's sort of remained to be a problem yet. When we receive some service, but we suddenly find out we haven't got any money on us usually we can leave a possession so that later we can pay the money and take that object back. I had these expressions from a friend: "to leave Sth as a pledge/ as collateral." Now, can we use "leave Sth in pawn" when it's NOT for borrowing money? (especially when we receive a service for which we haven't got the money) Thanks.
When you pawn something, it means you take something of value (jewelry, a television set, stereo equipment, etc) to a pawn shop and the pawn shop will give you a certain amount of money in exchange for the item. The amount he gives you will never be the full amount of what the item is worth, but he will keep your item for a set amount of time (30 days, perhaps) during which time you can buy it back for the same amount. Otherwise, after the prescribed time he will put your item up for sale in his shop.
In US slang, when we sell an item to a pawn shop we say that we "hocked" it.
(I go to a petrol station cos I need Sth for my car. I get the item but I realise I haven't got the money. As the seller doesn't know me, the only way is for me to leave Sth there, till I pay the money back.) (I know nobody does such a thing nowadays unless the seller is unapproachable! I just happened to be interested in the idiom or whatever that is. Thanks again.)
I would say you left something there on deposit or as collateral.
For example, at a water park, you can borrow a life jacket (at no charge) as long as you leave you driver's license there. You have leave your license as collateral. When you return the life jacket, you get your license back.
I'm not a teacher, but I write for a living. Please don't ask me about 2nd conditionals, but I'm a safe bet for what reads well in (American) English.