On April 1st the westerners like to play________on each other but they make sure that no one is hurt.
My teacher _____ me the key to the classroom but I’m afraid I _____ it.
---John and Tom, you two clean the classroom today, _____? ---But we cleaned it yesterday.
Pleasant as they made it ______ in Jiuzhaogou, we felt tired after the long journey.
Although the police thought he was the most likely one, _____ they had no exact proof about it, they could not arrest him.
As we know, _____ medical examination will help us find out health problems as early as possible.