1. at ten o'clock, at 2.15 p.m.
2. on Monday, on Tuesday
3. on Monday morning, on Tuesday afternoon
4. at the weekend, at weekends
5. at Christmas, at Easter
6. in January, in February
7. on 1st May, on 7th June
8. in 1930, in 1992, in 2001
9. in the summer, in the winter
1. at ten o'clock, at 2.15 p.m.
2. on Monday, on Tuesday
3. on Monday morning, on Tuesday afternoon
4. at the weekend, at weekends
5. at Christmas, at Easter
6. in January, in February
7. on 1st May, on 7th June
8. in 1930, in 1992, in 2001
9. in the summer, in the winter