"on" or "in" the morning of September 11th?

English as a Second Language English Vocabulary, Grammar and Idioms
1

Which preposition can be used in the following context?

b the morning of September 11th?[/b]

Thanks!

2

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‘On the morning of September 11th’. The date is the key reference. ‘On’ a day, ‘at’ a time, ‘in’ a month, year, etc.
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3

Thanks Mister for your reply.

I was confused because we have “in the morning”, “in the afternoon”, and “in the evening”.

4

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Yes, it is confusing. I often have to rely on my instinct.
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