gold coin

例句：

1. 1. The old man was given a gold coin as a reward for his hard work.
   那位老人因辛勤工作而获得了一枚金币作为奖励。
2. 2. The gold coin is worth more than the price of the house.
   这枚金币的价值超过了房子的价格。
3. 3.He kept the gold coin safe in his wallet until he could sell it.
   他将那枚金币安全地保存在钱包里，直到他能够出售它。