first grade 前面要加“the”吗?例如：She is a first grade students.He is in the school from the first grade to the eight grade 这句又加"the" 了到底什么时候加，什么时候不加？

first grade 前面要加“the”吗?例如：She is a first grade students.He is in the school from the first grade to the eight grade 这句又加the 了到底什么时候加，什么时候不加？ What grade are you in?I'm in first grade,first前为什么不加the呢? It is first October.读时first前面加the吗? ”我是第1个”的英语是I'm first 还是要在first前面加一个the? first and foremost 前面可以加the吗 Let's see □ lions first lions前面要不要加定冠词?也就是说,是Let's see the lions first还是 Let's see lions first? first前面加什么冠词 world前面要加the （高一）十年级：I'm in tenth grade,前面为什么不加the 请详细说明理由. 在第一天用英语怎么说?the first day 前面用不用加介词?加什么? who was first in the high jump?请问这句话first前面为什么不加the first表示第一的时候不是应该加the吗? the first grade 前用get 还是start they win first prize.first前要不要加the? 不定冠词the CCTV前面要加the? First impressions are the most lasting.求英语大神,我先知道这句话为什么前面没有the?谢谢!急啊！！！序数词前不是要加the吗？？？ first为什么有时前面不加the,比如It's my first time to play computer games. first and formost 前面加the 算很严重的错误吗 first day前要不要加the?是The first day 还是直接说First day?