I could tell he was surprised from the_____ on his face.

For some students, the computer serves only _____ a tool that is used to play games

Foreign teachers would like students to___ ask questions, submit theories, or to debate any required reading material[ ]

I’m exhausted. I ______ on a design day and night.–You’d better have several days off after finishing it. Otherwise you might break down.

No matter how frequently _____ the works of Beethoven always attract a large number of people.