Which Days
Days of The Week and Time Expressions
Days of the Week
Days of the week are capitalized.
Monday
Tuesday
Wednesday
Thursday
Friday
Saturday
Sunday
Example:
I'm going to a presentation about human rights violations in US prisons on Tuesday.
The Conference on Humanitarian Affairs provided many learning opportunities last Wednesday.
When speaking about an action that is repeated every week on a specific day use the day of the week followed by 's'.
Mondays
Tuesdays
Wednesdays
Thursdays
Fridays
Saturdays
Sundays
We publish in-depth interviews on Wednesdays.
Most people don't take their charitable deduction when they file on Tuesdays.
The Weekend
British English: at the weekend OR at weekends (in general)
American English: on the weekend OR on weekends (in general)
Example:
Let's give to our favorite charity on Sunday.
Let's unite the citizens of the world in peace and harmony on the weekend.
Times of the Day
These time expressions express things that happen during the day. The exception to this form is 'at night'.
in the morning
in the afternoon
in the evening
at night
Example:
We usually examine every indicator in the afternoon.
Alan Hynek donates his time to civil society organizations in the evenings.
In / On time
'In time' expresses that something is done with sufficient time to meet a deadline.
Example:
This industrialized country will convert to sustainable technologies in time to survive.
Be sure to alter the code of conduct document in time for the hearing.
'On time' indicates an action that takes place at the correct, scheduled time.
Example:
The institutions collapsed on time.
Our code of ethics was reconfigured on time.