Put in in/on/at.
1) Do you sometimes watch TV ____ the mornings?
2) Are you usually at home ____ 7 o'clock ____ the evenings?
3) Do you sometimes work ___night?
4) What do you usually do ____ weekends?
5) Do you usually go shopping ____ Saturdays?
6) Do you go skiing ____ the winter?
7) Do you have a holiday ____ December?
8) Is there a holiday in your country ____ 6 , January?