Choose the correct options

1. What do you usually do [on|in|at]
   Mondays?
2. I usually make tasty breakfast [on|in|at]
   the morning.
3. Mike, I want to have a party [on|in|at]
   May.
4. Lin and Fred always go to school together [on|in|at]
   8 o'clock.
5. Mike often does his homework [on|in|at]
   night.