Choose the correct answer to complete each sentence.
1. My grandfather often reads newspapers in/ on/ at the morning.
2. The new movie will be shown in/ on/ at Saturday evening.
3. Anna's birthday party will be held in/ on/ at 8 p.m. Don't be late!
4. Do you have free time in/ on/ at June 25th? - I'm going camping with my friends. What's wrong?
5. He was born in/ on/ at the spring of 2008.