He was deep in thought with his eyes_____ on the ceiling.

He said______ his sister had passed the entrance examination of college, and______she would go to college in about 20 days. 

The employees consider their boss unfair and unreasonable because he is not _________ in dealing with company affairs.

Evidence obtained from observation and experiment is often used to _____ a scientific theory.

45. —Could I borrow your digital camera, please? —Yes, of course you ________.