Thousands of years ago people discovered the phenomenon by chance, and this was _____ the idea of the compass first came from.
I hear that you will go to Beijing this afternoon. Who ______ you off at the airport?
—How long have you been working as an assistant here?—__________I finished middle school.
Mary is a good girl, but she has some___________. For example, she doesn’t like helping others.
This is the office ________ my parents are visiting now.
The manager of the company asked ________.