Collecting coins (cost\costs?)time and money because old coins are very hard to get.
问题描述：
Collecting coins (cost\costs?)time and money because old coins are very hard to get.
选COST为什么不加S呢?
答
你好.作为谓语动词,cost后面必须加s,因为Collecting coins做主语是单数第三人称的概念.你的句子可以改写成：It costs time and money to collect coinsbecause old coins are very hard to get.你看见了吗,it 是主...