After school, they usually play _____ football for an hour on _____ playground.

These natural parks are very important for preserving many animals, which would _______ run the risk of becoming extinct [ ]

________ all my family, I sincerely thank you for what you have done for us

When Tim returned home ten years later, we found he changed so much that we could hardly _____ him. [ ]

The police were seeking more information to find out ______ the rich merchant. [ ]