currency

美元是一种坚挺的外国货币。

The dollar is a strong foreign ___currency.

带上当地货币，以防你想买东西。

Take local ___currency in case you want to buy something.

一个国家的货币价值相对于其他国家可能会发生变化。

The value of a country's ___currency can change compared to others.