-- Have you known each other for long?--- No, not very long, ____ we started to study at the college.
At first I regretted _____ them to stay, but we soon became great friends.
Most of my friends shop at the stores _____ the goods are very cheap.
We climbed higher _____ we might see the scenes better.
According to the factory safety rules, all accidents _____ be reported to the safety officer.
John seemed puzzled about _____ the question meant.