Let's meet on/at 3 o'clock.
at
Wash your hands on/before dinner.
before
Hugo goes shopping after/on Saturdays.
on
I did my homework in the morning after/before school.
before
He was tired on/after work.
after
In/On the morning I eat breakfast.
In
I love to watch Netflix at/on 3 o'clock.
at
He loves to play basketball in/at the afternoon.
in
