Fill in the blanks with the correct prepositions. Each preposition has its own secret number:

• at = 1
• in = 2
• on = 3
• _ (no preposition) = 4

Write down the numbers in the correct order to get a 13-digit code and unlock the safe!

1. Lucy is arriving ____ February the 13th ____ 8 o'clock ____ the morning.
2. The weather is often terrible in London _____ January.
3. It's better to get a taxi if you are out alone _____ night.
4. She got married _____ September.
5. They usually go to the south of France _____ the summer.
6. Columbus sailed to the Americas _____ the 16th century.
7. The Beatles were popular _____ the 1960s.
8. I graduated from university _____ 2001.
9. His birthday is _____ June.
10. I usually go to my parents' house _____ Christmas. We eat turkey together _____ Christmas Day.