Learn English – How to use “the day of the week” properly

prepositionstimetime-words

After having done some research, here are my understandings of the uses of "the day of the week", but I am not sure I am right.

First Source:

with a singular day of the week to refer to one occasion:

I’ve got to go to London on Friday.

with a plural day of the week to refer to repeated events:

The office is closed on Fridays. (every Friday) In informal
situations, we often leave out on before plural days:

Do you work Saturdays?

Second Source:

Normally, "Monday", etc are nouns. However, In American English,
"Monday" could be an adverb & "Monday (adv)=on Monday"

I'll ring you Monday

Similarly, "Mondays (adv)=on Mondays"

The restaurant is closed Mondays

Third Source

a Monday (=one of the Mondays in the year)

My birthday’s on a Monday this year.

So, based on the 3 above rules, I would think these following sentences are correct:

I often do yoga on Mondays (repeated event)

I often do yoga Mondays (repeated event)

I will do yoga on Monday / next Monday (one occasion)

I went to Paris on Monday (one occasion)

However, I don't understand, why oxford dictionary has these example

On Monday(s) (= Every Monday) I do yoga.

On Monday I do yoga. (repeated event) —> is this correct?

I always do yoga on a Monday. (repeated event) —> is this correct?

I work Monday to Friday. (repeated event) —> is this correct?

Best Answer

In casual conversation:

On Monday I do yoga

could mean either this coming Monday, as in:

I can't come to the concert because on (this coming) Monday I do yoga

or every Monday:

I can attend choir practice any day except (each) Monday when I do yoga.

It's correct to state:

I always do yoga on a Monday (repeated event - although the a is often elided.

Regarding work on weekdays, people will say either:

I work Monday to Friday (repeated event)

or

I work Mondays to Fridays (repeated event).

Both are quite acceptable.

Related Topic