The dollar finished the day slightly down.
當日結束時美元匯率略有下降。
What's the rate of exchange against the dollar?
與美元的兌換率是多少？
Here's a five dollar bill ─ please keep the change.
這是一張五元的鈔票——零錢就不用找了。
If you want the best, you have to pay top dollar.
你想要最好的，就得花大錢。
The US dollar went through a difficult time, in company with the oil market.
美元與石油市場同時經歷了艱難時期。