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今天是星期天,我们去公园吧。
Today is Sunday, let's go to the park.
The seventh day of the week, following Saturday.
这个星期天我们有家庭聚会。
We have a family gathering this Sunday.
她每个星期天都去教堂。
She goes to church every Sunday.
星期天 is commonly used in spoken Chinese, though 星期日 is more formal in writing.
In northern China, 星期天 is more commonly spoken, whereas 星期日 is often used in southern China and formal contexts. Both mean 'Sunday'.
星期天 is always the last day of the week in Chinese context (Monday to Sunday).
星期 (week) + 天 (day). The term combines the concept of a week with the word for day.
星期天 is widely used in daily conversation, while 星期日 is preferred in formal writing. Both are interchangeable in most contexts.