But many people still eat very long noodles for their birthday.birthday为什么不加s变复数?
问题描述：
But many people still eat very long noodles for their birthday.birthday为什么不加s变复数?
答
eat very long noodles for their birthday.birthday
答
因为一个人只有一个生日.
如果你用其他的比如宠物就用复数了嘛.