that day/on that day

[dido4]

Hi,

1.What are the differences between that day and on that day?

2.Would you please give me some examples?

Thank you very much.

[Mister Micawber]

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They are often synonymous: We are moving to Kobe (on) that day.

Only that day can operate as a subject or object: I circled that day on my calendar. That day will always remind me of you.
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