The first day in a week is Sunday.

一周的第一天是星期天。

youdao

Our National Day is on the first day in October.

我们的国庆节在十月的第一天。

youdao

We will spend the first day in Disneyland and two days in Hollywood, and we will go to the beaches for the other two days.

第一天我们会在迪斯尼乐园度过，然后在好莱坞呆两天，接下来两天我们会去海滩。

youdao

He was sick only two days. They found him the morning of the first day in his room downstairs helpless with pain.

VOA: special.2009.08.01

On their first day of class in the fall of 2007, we have 41 students in our class this year.

007年秋天，开课第一天，今年一共收录41名学生。

哈佛公开课 - 幸福课课程节选

I announced on the first day of class that I don't, myself, believe in the existence of a soul.

第一节课上,我就声明,本人并不相信灵魂的存在

耶鲁公开课 - 死亡课程节选

She was a writer on the show, and I met her the first day in my interview.

WHITEHOUSE: Our Top Stories

The salvage operation at the disaster site wound down on Monday, the first day in which workers didn't find a corpse.

WSJ: Promises in Bangladesh

Lucie and Indian River counties, 6, 688 people already had opted for early voting, compared with 1, 088 on the first day in 2004.

CNN: Early voting suggests 2008 may see record turnout, expert says