I’d like to know if you could change this money back into U.S. dollars for me.
我想知道能否把这笔兑回成美圆。

Could you change these French francs for me?
能给我兑换这些法国法郎吗？

Can you give me 100 dollars in Swiss francs?
能否给我100美圆的瑞士法郎？

I’d like to convert the full amount of the remittance into U.S. dollars.
我想把全部汇款换成美圆。

I’d like some coins for this note.
我想把这张纸币换成硬币。

I’d like to break this 50 dollar note.
我想把这张50美圆纸币换开。

Five twenties and ten singles, please.
请给我5张20元和10张一元的。

I need 300 dollars in 100-dollar cheques.
我要300美圆票面为100美圆的支票。

I hope you’ll give me ten traveler’s cheques of 100 dollars each.
我希望给我10张面额为100美圆的旅行支票。

In fives, please.
请给我5元票面的。

Could you give me some small notes?
给我一些小票好吗？
　
Useful Words and Phrases
currency, money 货币
money changing 兑换货币
an exchange form 兑换单
bank note 钞票
note of large denomination 大票
note of small denomination 小票
small change 零钱
subsidiary money 辅币
nickel piece 镍币
plastic currency notes 塑料钞票
convertible money 可兑换（黄金）纸币